














































































Bulletin 73 


Mineral Technology 4 

DEPARTMENT OF THE INTERIOR 

FRANKLIN K. LANE, Secretary 

BUREAU OF MINES 

VAN. H. MANNING, Director 

BRASS-FURNACE PRACTICE 

IN THE 

UNITED STATES 


BY 

H. W. GILLETT 


















/ 


ST3 *- 

7/7 



✓ 





























































Bulletin 73 Mineral Technology 4 

DEPARTMENT OF THE INTERIOR 

FRANKLIN K. LANE, Secretary 

BUREAU OF MINES 

VAN. H. MANNING, Director 


BRASS-FURNACE PRACTICE 

IN THE 

UNITED STATES 


BY 


H. W. GILLETT 



WASHINGTON 

GOVERNMENT PRINTING OFFICE 
1916 



/ 


• * ^ 





The Bureau of Mines, in carrying out one of the provisions of its organic act—to 
disseminate information concerning investigations made—prints a limited free edition 
of each of its publications. 

When this edition is exhausted copies may be obtained at cost price only through 
the Superintendent of Documents, Government Printing Office, Washington, D. C., 
who is the authorized agent of the Federal Government for the sale of all publications. 

The Superintendent of Documents i* not an official of the Bureau of Mines. His is 
an entirely separate office and he should be addressed: 

Superintendent or Documents, 

Government Printing Office , 

Washington, D. C. 

The general law under which publications are distributed prohibits the giving of 
more than one copy of a publication to one person. Additional copies must be pur¬ 
chased from the Superintendent of Documents. The cost of this bulletin is 45 cents. 


Second edition. June, 1916. 

First edition issued in March, 1914. 


D. of D. 

337 H 19ft 


PREFACE. 




<£> 

V * 


In the preliminary investigations of the Bureau of Mines on the 
elimination of waste in our miscellaneous mineral industries, it early 
became apparent that there were big losses in the melting of the non- 
ferrous alloys. In order to investigate this matter more fully, the 
cooperation of the American Institute of Metals and of the chemical 
department of Cornell University, Ithaca, N. Y., was enlisted. This 
cooperation was heartily given, and special acknowledgment is hero 
made of the helpful enthusiasm and advice of Prof. W. I). Bancroft, 
and the interest shown by the members of the institute through 
whom a large part of the information presented in tliis bulletin was 
received. 

The object of the investigation reported in this bulletin was to 
ascertain the melting and fuel losses in present brass-melting prac¬ 
tice and to indicate, as far as possible, methods by which these losses 
might bo reduced. Dr. II. W. Gillett, alloy chemist of the Bureau of 
Mines, was assigned to the investigation. 

^There are in America to-day some 3,600 plants melting brass and 
bronze, and 1,000 of these melt nonferrous alloys exclusively. The 
alloys of copper, zinc, tin, lead, or other elements in cast or wrought 
form play an important role in our daily life. Allowing for the present 
recovery of waste metal, it appears that in current practice, between 
the purchase of the raw metal and the completion of the finished 
product, at least 5 per cent of the original metal is lost. Zinc passes 
into the atmosphere through the furnace stack; the other metals in 
the alloy maybe oxidized and pass into the stack, may be spilled in 
the furnace ashes, or in one way or another may not bo completely 
recovered. 

In the melting of nonferrous alloys, taking into consideration all 
such alloys and all furnaces and fuels used, it is shown that from 90 
to 95 per cent of the heat units in the fuel do no useful work. On 
the basis of $120,000,000 being the value of the metal passing through 
brass and bronze furnaces each year, a 2 J per cent melting loss, equiv¬ 
alent to 5 per cent loss on metal bought, means an annual loss of 
$3,000,000 in metal alone. Simply reducing the averago metal loss 
to that of present best practice would mean a saving of over $1,500,000 
a year. If fuel efficiency and crucible life could bo brought from 
present average to best practice, half million dollars more, at least, 
could be saved. 


44712°—Bull. 73—16 


1 


hi 




IV 


PREFACE. 

Ono of the most striking facts to which attention is called by this 
investigation is the lack of proper control and of proper records in 
most of our furnace practice. Of the 1,050 plants to which Dr.Gillett 
sent the list of questions, only 230 sent any data and about 60 of those 
stated that no records wore kept. Few of the plants that replied are 
under technical control, and it may be fairly assumed that the figures 
given in tliis bulletin represent the best practice in the United States. 
Dr. Gillett has concluded that it is doubtful if there are 50 firms in 
the country that have daily furnace records that are exact enough to 
allow the correction of avoidable losses. The firms that keep proper 
records, and hence have the necessary knowledge, invariably employ 
a trained metallurgist to supervise the melting furnaces, and these 
firms almost always have the lowest losses. That there is wide lack 
of technical control is emphasized by reports of metal losses varying 
from one-tenth of 1 per cent to 22 per cent and fuel efficiency from 
1 \ per cent to 1G per cent. The need for thorough technical control 
in the majority of our foundries and casting shops has been made 
evident by tliis investigation. 

Another waste not so readily expressed by figures but which none 
the loss really exists is the loss of efficiency of the workers in the 
industry through occupational disease and accidents due to a lack of 
safety precautions. A few of the firms reporting have given careful 
consideration to the prevention of disease and accidents, and it is 
shown that by the enforcement of simple, proper precautions occurni- 
tional disease may bo eliminated and the nonferrous alloy industry 
placed beyond reproach as to the health and safety of its employees. 

Investigation has also magnified the need of an efficient electric 
melting furnace in the alloy industry and a pyrometer which can be 
used as a workman’s tool. These two problems are now under inves¬ 
tigation by the Bureau of Mines. 

Another point that the work has particularly developed is the need 
of special studies of the absorption of gases, the speed of melting, the 
efTect of oxidizing or reducing flames, increase of crucible life, decrease 
of time of heating after melting, the efficiency of furnace linings, the 
utilization of waste heat, the strength of draft, the combustion space 
of furnaces, and the saving of metal from waste material. 

Tho important plants engaged in the nonferrous alloy industry 
opened their doors freely to tho employees of the Bureau of Mines 
during the progress of the investigation, and tho written data fur¬ 
nished were supplemented by personal visits which Dr. Gillett made 
to 80 foundries and rolling mills, in 13 States. Information was given 
freely, and it is hoped that tho results of the investigation will be of 
much value to the whole industry. 

Charles L. Parsons, 

( h i( f Division of itinera] Technology . 


CONTENTS. 


Page. 

Introduction. 9 

Magnitude of the brass industry. 9 

Losses of metal and fuel in melting brass and bronze. 10 

Monetary value of the losses. 11 

Object and method of the investigation. 13 

Methods of collecting data. 13 

"Reliability of data collected. 15 

Details particularly studied. 16 

General types of furnaces in use. 16 

No one “best” brass furnace. 16 

Electric furnaces used in experimental melts of brass, bronze, or copper.. 18 

General remarks as to classification of furnaces. 19 

General descriptions of furnace types. 19 

Pit furnaces. 19 

Natural-draft, pit, coke or coal furnaces. 20 

Forced-draft, coke or coal, pit furnaces. 20 

Oil or gas pit furnaces with burners. 21 

Tilting furnaces.1. 23 

Tilting, forced-draft, coke furnaces. 23 

Tilting, oil furnaces. 24 

Open-flame, tilting furnaces. 24 

Reverberatory furnaces. 26 

Cupola furnaces. 27 

Semiproducer furnaces. 28 

Furnace data from the literature. 30 

Natural-draft, pit, coke furnaces. 30 

Forced-draft, pit, coke furnaces.. 31 

Natural-draft, pit, anthracite furnaces. 32 

Forced-draft, tilting, coke furnaces. 33 

Pit, oil furnaces. 34 

Tilting, open-flame, oil furnaces. 36 

Reverberatory, coal furnaces. 38 

Gas furnaces. # 39 

Detailed results of investigation. 40 

• Explanation of tabulation of replies. 40 

General comments. 44 

Distribution of furnaces represented in replies. 120 

Output of different types of furnaces. 121 

Types of plants represented. 121 

Types of alloys melted. 122 

General factors affecting operation of brass furnaces. . 124 

Combustion. 124 

Oxidizing and reducing atmospheres. 124 

Volatility of zinc. 125 

Vapor pressure of molten brass. 126 


a 















































4 CONTENTS. 

General factors affecting operation of brass furnaces—Continued. Pu*e. 

Pressure of gases flowing over melting metal. 133 

Velocity of furnace gases. 136 

Volume of flue gases from various fuels. 136 

High-pressure gas. 140 

Covers and fluxes. 141 

Gases absorbed in melting metal. 142 

Speed of melting. 149 

Relation of w’eight of charge to melting speed. 152 

Crucible life. 156 

Proper treatment of crucibles in the foundry. 161 

Furnace linings and their life. 166 

Variation in fuel consumption with Bize of furnace. 168 

Melting losses. 170 

Round compared with square, pit, coal or coke furnaces. 173 

Relation of coal or coke space to fuel efficiency. 176 

Importance of draft in natural-draft furnaces. 177 

Furnace fuels. 178 

Comparison of metallurgical and by-product coke. 178 

Comparison ot coal and coke. 178 

Comparison of forced-draft and natural-draft coal or coke furnaces.... 179 

Liquid and gaseous fuels. 180 

Natural gas. 181 

City gas.'. 182 

Producer gas. 182 

Fuel oil. 183 

Rise in price of fuel oil. 184 

Tar. 187 

Remarks on furnace types and furnace parts. 187 

Natural-draft oil furnaces. 187 

Atomizing burners for oil. 187 

Steam atomization. 189 

Burners using liigh-pressure air. 190 

Combination burners. 191 

Burners using low-pressure air and high-pressure oil. 192 

Combustion space. 193 

Square oil furnaces. 195 

Open-flame furnaces. 195 

Open-flame furnaces for alloys high in zinc. 198 

Reverberatory furnaces. 199 

Oil-fired reverberatories. 199 

• Soft-coal reverberatories. 200 

I,arge furnaces for rolling mills. 201 

Possible improvements in furnaces and accessories. 209 

Development of the electric furnace. 209 

Metal losses in the electric furnace. 209 

Use of powdered coal. 212 

Gas combustion with theoretical air supply. 213 

Surface combustion. 215 

Use of heated ladle. 218 

Use of pyrometers for molten brass. 219 

Use of an accurate oil meter. 221 

Some furnace problems awaiting solution. 221 





















































CONTENTS. 


5 


Page. 

Advances possible with present equipment and knowledge. 222 

Utilization or recovery of wastes. 222 

Utilization of waste heat. 222 

Recovery of coal or coke from ashes. 231 

Use of borings. 232 

Briquetting of borings. 233 

Recovery of metal from waste materials. 234 

Methods used for rough separation of wastes. 235 

Recovery of zinc oxide. 242 

Standardization of alloys. 244 

Employment of a metallurgist. 247 

Applying scientific management to furnace practice. 249 

Proper choice of furnaces. 250 

Establishment of standards of furnace operation. 250 

Foundry records of furnace operations. 252 

Suggestions for furnace tests and records. 254 

Causes of disease and danger, and essentials for health and safety. 257 

‘ ‘ Brass shakes ”. 258 

Prevention of “brass shakes”. 264 

Proper ventilation. 266 

Maintenance of proper temperature. 268 

Lead and phosphorus poisoning in foundries. 269 

Metallic dust and similar irritants. 270 

Proper light in foundries. 272 

Prevention of burns. 273 

Treatment of burns. 277 

Danger from moving machinery. 277 

Danger signals. 278 

Bathing. 278 

Eating in the foundry. 279 

Miscellaneous equipment and precautions. 280 

Medical attendance and inspection. 281 

Proper period of labor. 281 

Fatigue and overstrain. 282 

Employment of women and children. 284 

Posted notices. 284 

General means of promoting safety. 285 

Welfare work. 286 

Summary of essentials for health and safety. 286 

Acknowledgments. 287 

Publications on mineral technology. 288 

Index. 291 





































































. 















' 

















ILLUSTRATIONS. 


Page. 

Plate I. Workman wearing goggles. • . 272 

IT. A, Right and wrong kind of shoes for foundry workers; B , shoe that 

allowed wearer to suffer a severe burn from hot metal. 274 

Figure 1. Vapor pressures of copper-zinc alloys. 127 

2. Approximate boiling points and assumed pouring temperatures of 

copper-zinc alloys. 129 

3. Relation of speed of melting to weight of charge in natural-draft, 

coke furnaces. 152 

4. Relation of speed of melting to weight of charge in natural-draft, 

coal furnaces. 153 

5. Relation of speed of melting to weight of charge in forced-draft, 

coke or coal furnaces. 154 

6. Relation of speed of melting to weight of charge in crucible, oil 

furnaces. 155 

7. Relation of speed of melting to weight of charge in pit, crucible, gas 

furnaces. 155 

8. Relation of speed of melting to weight of charge in open-flame, oil 

or natural-gas furnaces. 156 

9. Relation of speed of melting to weight of charge in reverberatory 

furnaces. 156 

10. Curves showing averages of data as to relation of speed of melting to 

weight of charge in five types of furnaces. 157 

11. Relation of size of crucible to its life, coal furnaces. 158 

12. Relation of size of crucible to its life, coke furnaces. 159 

13. Relation of size of crucible to its life, oil furnaces. 160 

14. Four types of crucible tongs. 162 

15. Relation between weight of charge and fuel consumption in natural- 

draft, coke furnaces. 169 

16. Relation between weight of charge and fuel consumption in natural- 

draft, coal furnaces. 170. 

17. Relation between weight of charge and fuel consumption in forced- 

draft, coke or coal furnaces. 171 

18. Relation between weight of charge and fuel consumption in crucible, 

oil furnaces. 172 

19. Relation between weight of charge and fuel consumption in open- 

flame and reverberatory oil furnaces. 172 

20. Curves showing averages of data as to relation of weight of charge to 

fuel consumption in five types of furnaces. 173 

21. Relation of net melting loss to zinc content of alloy melted. 174 

22. Covers for pouring crucibles or ladles, to hold back zinc fumes. 265 

23. Another type of cover for holding back zinc fumes. 265 


7 

































































liRASS-FURNACE PRACTICE IN THE UNITED STATES. 


By II. W. Gillett. 


INTRODUCTION. 

This bulletin is issued by the Bureau of Mines as a contribution to 
the increase of safety and efficiency in the preparation and utilization 
of the mineral resources in the United States. Notable among the 
drains on these resources are the demands made lry the nonferrous- 
metal industries, and in these the losses occasioned in melting brass 
and bronze are worthy of particular attention. This statement will 
be better appreciated by a consideration of the size of the brass 
industry. 

MAGNITUDE OF THE BRASS INDUSTRY. 

According to the Thirteenth Census, in 1909 there were in the 
United States 1,021 firms that dealt mainly in brass and bronze. 
This total included jobbing foundries, manufacturing plants that 
both cast and machine a brass or bronze product, and rolling mills, 
but did not include iron foundries having nonferrous departments 
nor the numerous large brass-foundry departments of manufacturing 
plants that produce the castings used in the manufacture of electrical 
apparatus, cash registers, pumps, and the thousands of machines 
that require brass castings for their construction. Pent on’s Foundry 
List for 1910 gives about 1,150 exclusively nonferrous foundries and 
about 2,300 iron or steel foundries that also melt brass. If the rolling 
mills and jobbing foundries in manufacturing plants he included, and 
if due credit be given to the rapid growth of the industry in the last 
few years, largely through the stimulation of the automobile busi¬ 
ness, it is probable that not less than 3,000 plants are to-day melting 
brass or bronze. 

The plants vary in size from the small shop using only one small 
furnace and employing only one or two molders to vast concerns 
melting ten, twenty, or even fifty million pounds of copper alloys a 
year. The alloys employed and their uses are legion, and the castings 
produced vary from tiny pieces weighing only a fraction of an ounce, 
such as buckles, up to huge 10-ton propellers for ocean liners. 


9 




10 BRASS-FITKNACE PRACTICE IN THE UNITED STATES. 

LOSSES OF METAL AND FUEL IN MELTING BRASS AND BRONZE. 

The lo*»s, both of metal and fuel, in melting brass and bronze bulk 
large. The net loss of metal, if all recovery of any sort be deducted 
and if all the brass and bronze alloys be included, will average not 
less than 2.5 per cent. Extreme figures reported are 22 and 0.1 per 
cent, the former figure being unusual and not representing regular 
practice and the latter not being verified. Extremes of 8 and 0.5 
per cent are well substantiated. The total melt will average about 
twice the raw metal bought, because of the remelt of crop ends and 
scrap in rolling mills and of gates and sprues in foundries. Some 
foundries making light castings melt 3 pounds of metal to get 1 
pound of castings. A ratio of 2 pounds of metal to 1 pound of castings 
is common, 0 and U to 1 is low. If, then, the whole industry be con¬ 
sidered, a loss ot 2.5 per cent on the gross melt is equal to about 5 
per cent on the raw metal bought. 

For the beat actually used in melting and bringing the metal up to 
an average pouring temperature, 140 kilogram-calories per kilogram 
(260 British thermal units per pound, or 26,000 British thermal units 
per hundredweight) of ordinary red brass is a liberal estimate, * 6 and 
yellow brass requires less. 

The following figures for heating values of the fuels ordinarily 
used in the foundry may he taken as close enough for purposes of 
calculation: 

IJcating valurs of furls used in the foundry. 

British thermal units. 

Coke, anthracite coal, bituminous coal.per pound.. 13,000 

Fueloil.do_ c 19,000 

Natural gas. per cubic foot.. 1,000 

City gas.do 625 

Producer gas.do 120 

On this basis, if all the heat units in the fuel could he utilized in 
heating the metal, no deductions being made for the presence of 
water vapor in the products of combustion (using the “high ” heating 
value), that is, with 100 per cent theoretical efficiency, it would take 
to heat 1 hundredweight of brass to a pouring temperature: Two 
pounds of coke or coal; 1.4 pounds, or 0.1S gallons, of oil; 20 cubic 
feet of natural gas; 41.5 cubic feet of city gas; 217 cubic feet of 
producer gas. 

The limits representing actual practice, as reported in replies to in¬ 
quiries incident to the investigation here outlined, are as follows: 

a Blair, P. W., Relation of metal cast to floor area of foundry: Metal Ind:, vol. 11,1913, p. 112. 

6 Richards, J. W., Electric power required to melt metals: Trans. Am. Brass Founders’ Assn., vol. 4, 
1910, p. 99; Hansen, C. A., Electric melting of copper and brass: Tnins. Am. Inst. Met., vol. o, 1912, p. 112. 

c Or 145,000 British thermal units per gallon. 








INTRODUCTION. 


11 


Quantity's of different fuels required to heat 1 hundredweight of brass to pouring temper¬ 
ature. 


Re- 

Ro. 

Fuel. 

Type of furnace. 

Fuel 
required 
per hun¬ 
dredweight. 

Per¬ 
centage of 
theoreti¬ 
cal heat¬ 
ing value. 

26 

Coke. 

Forced-draft tiltinp. 

Pounds. 

13 

15} 

1} 

133 

.do. 

Natural-draft pit. 

133 

21 

Anthracite coal 

.do. 

25 

12} 

115 

. do . 

Forced-draft pit. 

125 

1| 

11 

180 

B ituminous 

Forced-draft reverberatory. 

18 

202 

coal. 

.do. 

.do. 

88 

21 

79 

Oil. 

Reverberatory. 

Gallons. 

1.11 

*•4 

lf> 

150 

.do. 

Square-pit.... 

7.8 

2} 

13 

104 

Natural pas... 

Open-flame. 

Cubic feel. 
200 

145 

.do. 

Tilting crucible. 

480 

7} 

16 

108 

City pas. 

Pit. 

256 

12 

_'do. 

.do. 

650 

6} 

6 

164 

Producer gas.. 

.do. 

3,500 




Reply 154 (p. 104) reported the use of 7.5 pounds of coke per hun¬ 
dredweight in a forced-draft, tilting furnace, or 26 percent efficiency. 
This figure is doubtful, although some makers of that type of furnace 
claim that it needs only 6 pounds of fuel per hundredweight, an effi¬ 
ciency of 33 per cent of the theoretical. The lowest fuel consumption 
reported a for a natural-draft, pit furnace using coal or coke was 
20 pounds per hundredweight, or an efficiency of 10 per cent of the 
theoretical. For the oil furnaces figures were given very slightly 
above and below those noted above, but they could not be verified. 

The fuel efficiency is therefore seen to vary between 1J and 16 
per cent, the average being 4 to 9 per cent. If all fuels and all fur¬ 
naces be considered, it is doubtful whether the average fuel efficiency 
is more than 7 per cent of the theoretical. 

MONETARY VALUE OF THE LOSSES. 

In 1909, according to the Thirteenth Census, 6 1,021 establishments 
making brass and bronze products spent for materials $99,228,000. 
If it be assumed that 80 per cent of that amount was for metal, 
$80,000,000 is spent annually for raw metals in such establishments, 
which do not comprise a third of the whole number of firms that melt 
brass and bronze. 

No attempt was made to procure data on the tonnage melted, but 
10 firms—manufacturers of commodities listed under other headings 
in the census reports—did give such data, the total being 58,000,000 
pounds for the 10 firms, some of which arc not exceptionally large. 
If a ratio of melt to metal bought of 2 to 1 be allowed, tho figures 


a Reply 163. 


t> Thirteenth Census. Advance Bulletin, Statistics of Manufacturers, 1910, p. 75. 
















































12 


BRASS-FURNACE PRACTICE IN THK UNITED STATES. 


quoted moan that 29,000,000 pounds of lnotal was bought at a value 
of about $4,000,000. In view of the known size of other firms, not 
included in the Census classification under manufacturers of brass 
and bronze products but furnishing replies to inquiries, a conserva¬ 
tive estimate of the value of the metal bought by such firms would be 
about six times that bought by the 10 firms mentioned, or, say, 
$24,000,000, which, with the $80,000,000 for those that are included, 
makes $104,000,000 spent for metal by the firms included in the 
Census statistics and bv those furnisliing replies. As many other 
firms melting brass and bronze do not fall into either of these classes, 
it appears that the estimated value of all the metal used should be 
at least $120,000,000. 

The consumption of copper in the United States in 1911 was about 
080,000,000 pounds.® If two-thirds of this total, or 450,000,000 
pounds, be considered as having been used for making brass and 
bronze, and if the average copper content of the alloys used be 
assumed as SO percent, the deduction would be that about 500,000,000 
pounds of brass and bronze products was made from new copper. 
It seems conservative to estimate that at least two-thirds of the cop¬ 
per consumed in the country is in the form of brass and bronze, as 
Lathrop 6 states that one corporation making mainly wrought yellow 
brass uses in its various plants approximately a third of all the copper 
consumed in the United States. To this must be added the old metal 
used. Half as much old scrap or alloyed ingot as new metal, that is, 
280,000,000 pounds, c seems a fair estimate, so that 840,000,000 
pounds should represent the total metal bought. The average value 
of brass and bronze being taken at 15 cents a pound, by this method of 
figuring $12G,000,000 would be the value of the metal passing through 
the brass and bronze furnaces of the United States in a year. For 
purposes of computation the estimate of $120,000,000 has been taken. 

A 2 J per cent melting loss, equivalent to a loss of 5 per cent on the 
metal bought, thus means $3,000,000 a year lost in metal alone. 
Could this be reduced to the 2£ per cent loss (equivalent to 1 \ per 
cent on the melt) shown by good practice, a saving of $1,500,000 a 
year would result. If the fuel consumption and crucible life were 
brought from the average practice up to good practice, and if fur¬ 
naces that cut down or eliminate crucible cost and allow greater pro¬ 
duction with less labor cost were used wherever pract icable, a saving 
of at least another half million would be made, or a total of $2,000,000 
a year that the nonferrous-alloy industry of the United States might 

a Mineral Industry, 1911, p. 165. 

* Lathrop, W. 8., The brass industry of Connecticut, 1909, p. 127. 

* U. 8. Geological Survey Cress Bull. 117, The country’s enormous junk hoop, June, 1913, p. 2. The 
recovery of secondary copper by smelters and refiners in 1912 is here given as 137,507 tons. This figure is 
on copper and the copper content of the recovered brass. That for remelted brass (alloyed ingot) is 101 ,437 
tons, or nearly 203,000,000 pounds. Resides this, in foundries themselves there is a large remelt of old scrap, 
which does not reach the refiner. See also Foundry, vol. 41, 1913, p. 3K4. 




OBJECT AND METHOD OF THE INVESTIGATION. 


13 


save merely by bringing average furnace practice up to the standard 
of the best practice. 

However it be figured, it is certain that the statement that the 
problem of the wastes in brass melting is one of the greatest impor¬ 
tance in the conservation of waste in alloy manufacture® is correct. 

OBJECT AND METHOD OF TIIE INVESTIGATION. 

The object of the investigation here reported was to find out the 
melting and fuel losses in brass melting as practiced at present, and 
to indicate, as far as possible, the methods by which the losses may 
be reduced. To this end endeavor was made to collect data from as 
many plants melting brass as were willing to cooperate. Such data 
should serve not only to show the melter of brass what others are 
doing, and to allow him to compare his ow r n work with the practice 
of others, but also to show on what points further invention and 
improvements are needed, and thus servo as a guide in planning 
further investigations by the bureau. 

The cooperation of the American Institute of Metals was enlisted, 
and a large part of the information here recorded has been leceived 
from the members of that institute. 

METHODS OF COLLECTING DATA. 

A list of questions was sent to all members of the institute and to 
brass foundries and rolling mills in general. Questions were sent 
to every plant whose main business was known to be the production 
of brass, bronze, or similar alloys. The questions were sent also to all 
manufacturing plants known to melt these alloys in any considerable 
amount, to such iron foundries as w r ere known to melt a large enough 
tonnage of copper alloys to make it likely that the data desired were 
recorded by them, and to all the iron foundries in Penton’s list the 
firm name of which mentioned brass or bronze. 

In all about 2,000 lists of questions w T cre thus sent out. The 
questions asked were as follows: 

DATA ON MELTING FURNACES. 

[Cooperative investigations of the Bureau of Mines and the American Institute of Metals.] 

Please answer fully the following questions, making separate lists of answers for each 
type of furnace with which you have had experience. The basis for the figures is a 
working day for one furnace, as this can probably be most easily obtained from exist¬ 
ing records. 

1. What is the type of furnace (pit, tilting with crucible, tilting without crucible, 
electric) used? Maker’s name. 

2. Shape and dimensions of furnace. 

3. Lining—material, thickness. 

4. Cover—shape, size, and material. 

5. Size crucible used. 

6. What fuel used? 


a Parsons, C. L., Notes on mineral wastes: Bull. 47, Bureau of Mines, 1912, p. 20. 






14 


BRA8S-FURNACE PRACTICE IN THE UNITED STATES. 


7. I Mail* of fuel ami air supply. 

(а) For coal and coke furnace*- give grade of fuel used; also analyses and British 
thermal units per pound, if possible; wliat vacuum, if natural draft; wliat pressure, if 
forced draft. 

(б) For gas—state whether natural gas or artificial; British thermal unite jht cubic 
foot, if poHtuble; pressure of gas at burner; pressure of air at burner; type of burner. 

(c) For oil—give specific gravity, or degrees Bauin6, and temperature at which 
density was determined; British thermal units per gallon, if possible; pressure of oil 
at burner; pressure of air at burner; type of burner. 

(d) For electricity—give voltage and amperage taken by furnace, and other details, 
as jKiwer factor of furnace, etc. 

8. Number of furnaces one furnace tender can handle. 

(Answer questions 8 to 19 on basis of red brass.) 

9. Amount of fuel used per furnace per day—pounds of coal or coke, gallons of oil, 
cubic feet of gas, kilowatt-hours of electricity. 

10. Number of heats j>er working day. 

11. Hours per working day of furnace—from time cold furnace is started till day 
is over. 

12. How often are furnaces relined, or other repairs made? 

13. How many heats to the life of a crucible? 

14. Total pounds of metal charged per day per furnace; pounds of composition ingot; 
pounds of new metal; pounds of gates and sprues; pounds of borings; pounds of other 
scrap. 

15. Total pounds of metal poured per day per furnace, deducting all losses by 
oxidation or volatilization, or in the slag or skimmings. 

1G. Total pounds of metal recovered from slag, skimmings, etc., per furnace per 
day. 

w 

17. Gross percentage of loss during melting. 

18. Net percentage of loss during melting, taking account of metal recovered from 
all metal-bearing refuse. 

19. Average analysis of alloy produced. 

20. Answer questions 8 to 19 for yellow brass, manganese bronze, or any other brass 
or bronze you have figures for. 

21. Are your figures based on a single day’s run, or are they averages? If the latter, 
on how long a period is the average based? 

22. Discus the relative advantages and disadvantages of the various types of fur¬ 
naces you have tried. Is there any difference in the quality of the metal melted in 
various furnaces as regards physical tests, pressure tests, or as to its behavior in the 
foundry? 

23. Wliat precautions are taken to insure immunity of employees from accident, 
poisoning, or occupational disease? 

24. To what extent are employees subject to “brass shakes,” lead poisoning, etc.? 

25. What precautions are taken to lay or remove poisonous fumes or irritating dust 
to which employees may be exposed? 

2G. Do you post notices and give instructions to employees in regard to hazards to 
which they may be subject? If so please send copies of notices and of instructions. 

27. Please give any information along these lines you can that has not already 
been brought out by the questions. 

28. In what way is the waste heat from your melting furnaces utilized? Have you 
any concentrating system at work on ashes, sweepings, skimmings, etc., for the 
recovery of waste? 

Replies, so far as they apply to individual plants, will lie held confidential by the 
Bureau of Mines. 


OBJECT AND METHOD OF THE INVESTIGATION. 


15 


A letter accompanying the questions contained the following 
statement: 

The replies will be summarized for publication, but the communications themselves 
and the source thereof will be held strictly confidential. 

% 

About 350 such inquiries wore returned unanswered, the firms 
being out of business, or having abandoned their work in brass and 
bronze. Of the 1,650 “live” firms to which inquiries wore sent, 
about 280 replied, some 230 with data and some 50 with the state¬ 
ment that they kept no records that would enable them to give any 
data. Many of those replying gave figures for several types of fur¬ 
naces, so that the aggregate replies are equivalent to about 300 
fairly complete sets of data. The replies covered 28 States, the bulk 
of them coming, of course, from the States of New York, Pennsyl¬ 
vania, Illinois, Massachusetts, Ohio, Michigan, and Connecticut. 

- States as widely separated as Maine, Georgia, and Washington sup¬ 
plied data. 

The information obtained was supplemented by personal visits to 
some 80 foundries and rolling mills in 13 States. Admission was 
refused to only three plants, all rolling mills, one in New York City, 
one in Connecticut, and one in Massachusetts. At less than half a 
dozen plants, these also being mainly rolling mills, was information 
refused, the reason given being that the policy of the management 
did not permit the furnishing of information. The superintendents 
or chemists of most of these plants expressed themselves as desirous 
to cooperate, but unable to do so under the rules of the management. 

In general the foundries showed a great interest in the work, as 
did most of the rolling mills. 

It is believed that the data obtained represent the practico of the 
great bulk of the firms melting brass that keep records or make tests 
from which such data could be compiled. As the more progressive 
is the plant, the fuller the records that are kept, and the less the likeli¬ 
hood that easily preventable leaks are occurring, it is probable that 
the average practice of the firms not reporting is at least no better 
than the average of those that did report. 

RELIABILITY OF DATA COLLECTED. 

Tho information furnished varied in exactness and reliability. 
Some data represented estimates that were somewhat vague owing 
to lack of accurate records, the vagueness being greatest in tho most 
important points, the loss of metal in melting, and the fuel consump¬ 
tion. In many of these reports there may have been a desire to put 
the best foot foremost, so again, it is improbable that tho average 
in the plants reporting is any better than tho figures given. All 
replies received that were complete enough to bo of any value what- 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


1 (> 

over have boon included, as ovon estimates not based on actual accu¬ 
rate records, are, after all, estimates made by those in best position 
to know the facts. In some instances the records wore shown and 
the accounting system was explained; in others, the replies them¬ 
selves showed that the records were accurately kept. Many of the 
replies were either inconsistent in themselves, or so far at variance 
with ordinary practice as to call for comment. Further correspond¬ 
ence was had with the firms furnishing such replies, and many errors 
were subsequently corrected. A few of the replies (mentioned in the 
notes following the large tablo) were given on the question sheets 
and mailed without the firm name being furnished. If only a few 
letters had been sent to tho town or city shown by the postmark, 
further correspondence sometimes showed tho source of the replies, 
but if tho replies wore from large cities, identification was impossible. 

On tho wholo, it is believed that the figures tabulated herein are in 
the main correct and, as regards most types of furnaces, sufficiently 
numerous to reflect tho practice of the firms supplying them, the 
practice, as before stated, being probably better than the averago 
of the total number of brass molters in the United States. 

DETAILS PARTICULARLY STUDIED. 

An attempt has been made to study in particular the following 
important details: Gross loss in melting; not loss in molting; meth¬ 
ods of recovery of metal wasto; fuel consumption per hundredweight 
of metal melted; methods of utilizing waste heat from furnaces; 
most efficient construction of a given type of furnace; most efficient 
operation of a given typo of furnace; speed of melting (production 
per furnace per hour); furnace repairs; labor factor (metal melted 
per furnace tender per hour); effect of various types of furnaces and 
methods of operation on health and safety of the workmen; details 
requiring particular attention and further study as a step toward 
reducing waste. 

GENERAL TYPES OF FURNACES IN USE. 

NO ONE “BEST” BRASS FURNACE. 

One point must be made at the outset. Although tho investigation 
herein outlined dealt particularly with furnaces, the real problem, 
when all factors aro considered, is tho most economical heating of 
metal. Modern methods show that by eliminating the causes of 
hindrances and delays, as well as waste motions, and by establishing 
some suitable efficiency reward for the workmen, foundry produc¬ 
tion at many plants can readily bo made twice as large as that ob¬ 
tained by former methods. Hence tho furnaces aro called upon to 
supply far greater quantities of metal a day than has been necessary 
in tho past. If tho furnaces can not bo pushed so as to yield an 
increased supply, more furnaces must be put in, else the melting 


GENERAL TYPES OF FURNACES IN USE. 


17 


capacity will not bo properly balanced in regard to the molding spaco. 
Hence the problem of rapid melting of metal is equally as impor¬ 
tant as those of losses in melting and fuel efficiency. All factors must 
bo taken into consideration. 

Each foundry or casting shop is a problem in itself. Hardly two 
plants in tho country deal with exactly the same alloys or have 
exactly tho same lino of work. Tho proper furnaces for a plant 
making chiefly huge manganese-bronzo propellers may not bo by 
any means tho proper furnaces for ono making very light castings 
from red brass. Fuel and labor conditions vary widely with the 
location of tho shop. 

Consequently there can bo no such thing as one best brass furnace, 
nor even one best type. There probably is, however, for any given 
location and given set of conditions some best furnace or typo of 
furnaco. 

The furnaces can bo most readily studied by dividing them into 
types and then considering their applicability to different alloys and 
different shop conditions. 

Tho main types of furnaces in actual commercial use may bo 
grouped in several ways as to fuel used—into those using solid fuel, 
as charcoal, coal, or coke; liquid fuel, as fuel oil; or gaseous fuel, as 
natural, city, or producer gas. According to tho method of con¬ 
struction of the furnace, they might be classified into tapping, tilting, 
and pit furnaces, or into those using crucibles or not using them. In 
a more detailed classification, the following types might bo listed: 

General types offurnaces in use. 


No. 

Li eneral designation of type of furnace. 

Kind of draft. 

Fuel burned. 

1 

Pit. 

Natural. 

Coke. 

2 

.do. 

.do. 

Anthracite coal. 

3 

.do. 

.do.. 

Both coke and coal. 

4 

.do. 

.do. 

Both coal and charcoal. 

5 

.do. 

Forced.... 

Coke. 

6 

.do. 

.do. 

Coal. 

7 

.do. 

.do. 

Both coke and coal. 

8 

Tilting. 

.do. 

Coke. 

9 

.do. 

.do. 

Coal and coke. 

10 

Pit. 

Natural. 

Oil. 

11 

.do. 

Burner. 

Do. 

12 

.. .do. 

.do. 

Natural gas. 

City gas. 

Producer gas. 

Oil. 

13 

.. .do. 

.do. 

14 

.do. 

.do. 

15 

Tilting. 

.do. 

16 

.do. 

.do. 

Natural gas. 

Producer gas. 
Bituminous coal. 

17 

.do. 

.do. 

18 

Pit. 

Natural. 

19 

.do. 

Burner. 

Oil. 

20 

. .do. 

Natural. 

Do. 

21 

Open-flame tilting. 

Burner. 

Do. 

22 

* .do. 

.do. 

Natural gas. 

Oil. 

23 

Reverberatory. 

.do.:. 

24 

. .do . 

Natural. 

Bituminous coal. 

25 

. .do. 

Forced. 

Do. 

26 

Cupola. 

.do. 

Coke. 

27 

. /.do. 

.do. 

Charcoal. 

28 

Reverlteratory... . 

Burner. 

Producer gas. 

29 

.. .do.*. 

Natural. 

Oil. 

30 

Open-flame tilting . 

Burner. 

City gas. 




14712°—Bull. 73—16 






































































































18 


BHASS-FURNACE PRACTICE IN THE UNITED STATES. 


NOTES. 

Tvi>oa 1 to 20 um* crucibles; types 21 to 30 do not. 

Tyj >08 1 to 27 have boon used commercially in melting bran*. 

Types 18 and 19 take several crucibles per furnace. 

Tyj»e 28 has probably been tried experimentally. 

Type 29 is in use for melting nickel and copper scrap and may have been used for 
brass or bronze. 

Type 30 is in use for melting copper. 

Many other combinations of furnace and fuel are possible, but it 
is not known that they have been actually used in the United States. 
Other types suggested are the “semiproducer” furnace, burning 
bituminous coal, and furnaces burning powdered coal, either of which 
might be made in the crucible or reverberatory types. The former 
possibly and the latter certainly could also be made in the open- 
flame tilting type. The “surface or flameless-combustion” furnace, 
burning natural, city, producer, or other gas, is another suggested 
form which could be made in the crucible type and possibly in a type 
analogous to a reverberatory, either tapping or tilting. 

ELECTRIC FURNACES USED IN EXPERIMENTAL MELTS OF 

BRASS, BRONZE, OR COPPER. 

Experimental melts of brass, bronze, or copper have been made 
in the following types of electric furnace, with a view to commercial 
use: 

Experimental electric furnaces used in melting brass , bronze , or copper. 

1. Tit furnace, resistance type, carbon resistor in adjustable blocks, crucibles used. 
(Hoskins type.) 

2. Tilting furnace, resistance type, granular carbon resistor, crucibles used. 

3. Fit or tilting furnace, resistance type, solid, molded resistor, crucibles used. 
(Helberger and Conley types.) 

4. Tilting (or tapping) reverberatory-type furnace, solid resistor in blocks, ad¬ 
justable or nonadjustable, no crucibles. (Hoskins and Fitzgerald-Thomson types.) 

5. Tilting furnace, indirect arc, no crucibles. (Stassano type.) 

6. Tilting furnace, arc to slag, or slag resistance, or both, no crucibles. (Iltfroult, 
Snyder, and Wile types.) 

7. Tilting (or tapping) furnace, pinch effect, resistance in molten metal, no cruci¬ 
bles. (Bering type.) 

8. Tilting (or tapping) furnace, induction, resistance in molten metal, no crucibles. 

An electric crucible furnace using a granular chromium resistor 
has been tried or suggested for experimental work. A tilting-crucibio 
furnace with a metallic resistor has been partly or wholly designed 
with a view to commercial use. At present in the United States there 
seem to he no electric furnaces in regular commercial use for melting 
brass, bronze, or copper, though one is in use for an alloy of nickel 
and chromium. Electric furnaces for melting steel are, of course, in 
extensive commercial usc. a 


• Humor W. A., Progress of the electric steel industry: Jour. Ind. Kng. Them., vol. 5, 1913, p. 866. 






GENERAL TYPES OF FURNACES IN USE. 


19 


GENERAL REMARKS AS TO CLASSIFICATION OF FURNACES. 

Other subdivisions of the types classified above might well be made 
as to shape, as both round and square furnaces of the following types 
are in use: Natural-draft pit coal, natural-draft pit coke, forced- 
draft pit coke, forced draft tilting coke, and pit oil. There are also 
used commercially at least four shapes of tilting open-flame oil or 
natural-gas furnaces. 

The pit and tilting furnaces using crucibles with oil burners could 
be greatly subdivided according to the shape of the combustion 
chamber, and these as well as reverberatory furnaces with oil burners 
should be divided according as to whether the oil is vaporized mainly 
by its own pressure, by high air pressure, or by steam pressure. Other 
divisions might be made according to the make of the furnace, par¬ 
ticularly in the tilting, forced-draft, coke furnaces, pit and tilting, oil 
or gas, and open-flame oil or gas furnaces, but the furnaces are here 
considered according to types rather than according to make. 

More or less information has been procured on all the 27 commer¬ 
cially used types, and information complete enough for tabulation 
has been obtained on all but Nos. 9, 17, 18, 20, 26, and 27 of the above 
list. 

Nos. 3, 4, and 7, which burn mixed fuel, have been included under 
the predominant fuel, note being made that mixed fuel was used. 
After having taken into account the shape of a given furnace, whether 
the oil is vaporized mainly by its own pressure or by high-pressure 
air (steam being included under high-pressure air, and an air pressure 
of 2 pounds per square inch at the burner being taken as the dividing 
line), and whether the alloy melted is high or low in zinc content (10 
per cent of zinc being arbitrarily taken as the dividing line), it has 
been found advisable to divide the data received into a tabulation 
with 39 subdivisions for ease in comparison. 

GENERAL DESCRIPTIONS OF FURNACE TYPES. 

PIT FURNACES. 

Under pit furnaces, as a convenient name, are herein included all 
furnaces using a single crucible from which the crucible is lifted and 
carried bodily to the mold for pouring, whether the furnace itself is 
beneath the floor levd and in an actual pit, whether partly above and 
partly below the floor level, or wholly above the floor level. The 
last form is sometimes called the “crucible lift-out.” If the furnace 
is below the floor level and square, it is made of brickwork, reinforced 
by iron girders; if round, it is made of circle brick, usually set in an 
iron or steel casing, the whole being placed in the pit. In the lift-out 
form the iron or steel casing is practically always used. 


20 BRA88-FURNACE PRACTICE IN TIIK UNITED STATES. 

NATURAL-DRAFT, PIT, COKE OR COAL FURNACES. 

A characteristic construction of pit furnaces burning hard coal or 
coke under natural draft is a pit about 6 to 8 feet deep, of about the 
same width, and as long as the battery of furnaces. The width is 
divided about equally into runway and furnace setting. The runway 
for removing ashes is covered with an iron grating or iron plates. 
Transverse iron girders 3 or 4 feet from the bottom of the pit support 
the furnaces and setting. The furnaces are side by side, built of tire* 
brick, each furnace usually having walls about 4 inches thick. The 
furnace bottoms consist of iron grate bars, usually hinged so as to 
drop any fuel and ash left on top of them into the pit below, and 
controlled by chains from the melting floor above. From a few 
inches to a foot from the top, at the back of the furnace, is a rec¬ 
tangular or square flue, which leads into a larger flue running back of 
the battery, this larger flue in turn leading to the stack. Fuel is 
placed on the grate bars, the crucible is set on the fuel, and more fuel 
is piled around the sides of the crucible, so that the coal or coke comes 
in direct contact with the crucible. A variously shaped cover, often 
of cast iron in dome shape or flat, of fire brick in an iron frame, of a 
solid fire-brick slab, or of cast steel or manganese steel, is provided, 
which may be swung aside, lifted ofT, or rolled back. 

At some plants dampers arc placed in the flues to cut out any fur¬ 
naces not in action, or the flues in inactive furnaces may be plugged. 

Pit furnaces for brass and bronze vary in capacity from 25 to 1,000 
pounds. The average capacity is probably about 180 to 240 pounds. 

Bramit® and Japing and Krause 6 discuss an old kilnlike form of 
coke-fired furnace containing several crucibles set in the fuel bed, 
the central or “ king” crueiblo being surrounded by smaller ones, and 
tho whole being covered with a dome-shaped roof leading to a stack. 
This was used for melting and mixing copper and zinc, but was plainly 
an outgrowth of the old form of furnace previously used in making 
calamine brass, in which calcined calamine ore (zinc oxide) and coal 
dust wero mixed and charged into crucibles between successive 
layers of shot copper, and tho crucibles slowly heated, when tho zinc, 
reduced from tho ore, distilled up through and alloyed with tho cop¬ 
per, the charge melting to brass. This form of furnace evidently 
did not long survive tho calamine process which is now merely of 
historical interest. 

FORCED-DRAFT, COKE OR COAL, PIT FURNACES. 

The arrangement for stationary pit furnaces burning coal or coke un¬ 
der forced draft does not differ greatly from tho ordinary natural-draft 
form, save that instead of tho ash pit being open to the air below the 
grate bars, it is inclosed so that air under pressure may be led into it. 


" Brannt, W. T., Metallic Alloys, 1896, p. 162. 
b Japing, E., and Krause, II., Kupfer und Messing, 1912, p. 64. 







GENERAL TYPES OF FURNACES IN USE. 


21 


OIL OR GAS PIT FURNACES WITH BURNERS. 

Pit furnaces for use with ordinary oil burners, or with burners for 
natural, city, or producer gas, closely resemble the coal or coke pit 
furnaces. They are almost invariably built with an upright, cylin¬ 
drical chamber (or very rarely with one of square cross section) for 
the crucible, from circle bricks or ring blocks held in a drumlike iron 
or steel shell. They may be sunk in a pit, flues to a stack being pro¬ 
vided as in coke-pit furnaces. Many, however, are partly or wholly 
above the floor level and the products of combustion are carried off 
either by piping or by mere hoods hung overhead and attached to 
short steel stacks. Few of the covers are solid, as are normally those 
of coke, pit furnaces, but most of them have a hole in the center 
through which metal may be charged into the crucible. The crucible 
is set on a refractory crucible block and is thus raised a few inches 
from the bottom of the furnace. The burner is introduced through a 
hole near the bottom of the furnace, sometimes pointing directly 
toward the crucible, but as often tangentially, so as to produce a 
whirling flame that will encircle the crucible several times before 
emerging. In one make a spiral baffle is put between the furnace 
wall proper and the crucible, and the burner is at the bottom in order 
to give the whirling motion; in another, the burner is at the top and 
directed downward into a combustion chamber that is beside the 
furnace proper and is an enlargement of it, making a chamber some¬ 
what oval in plan, with the crucible placed eccentrically. In other 
types a chamber is used that is pear-shaped hi plan, with the burner 
entering from the side. In others, the burner is introduced into a 
cylindrical combustion chamber, placed horizontally to the vertical 
and larger cylindrical furnace chamber proper and attached to it near 
the bottom. In all of these designs the intent is to allow adequate 
combustion space and to bring the hotter part of the flame about tho 
crucible instead of merely at its top or actually outside of the furnace. 

Tho forms of oil burners used with these furnaces are legion. The 
United States Naval Liquid Fuel Board reported in 1904 that 
thousands had been patented then, and inventors of burners have not 
been idle since 1904.“ The burners in foundry use may, however, 
be divided into two general classes—those using air at comparatively 
high pressures, an arrangement that both gives air for the combustion 
of the oil and atomizes the oil, and those using low-pressure air for 
combustion and atomizing the oil by pumping it at comparatively high 
pressure through a sufficiently small orifice in the burner. In some 
furnaces the air is preheated before delivery to the burner bv bringing 
the inlet pipe through the flue through which the products of combus¬ 
tion pass; or the air may be passed around the furnace casing itself, in 


a Report of the United States .Naval Liquid Fuel Board, 1904, p. 340. 








oo 


B HASS- PUBNACE PRACTICE IN TIIK UNITED STATES. 


a hollow shell, or through h series of return bends in the inlet pipe, 
which is brought through the path of the hot products of combustion. 
The oil is seldom heated, except back of the pump in winter, and then 
only enough to make it fluid enough for the pump to handle, although 
in a few furnaces the oil is slightly preheated just before it enters the 
burner. 

Pit furnaces using natural gas differ in no vital essential from those 
using oil, savo in the burner used. Those using city gas are sometimes, 
and those using producer gas must almost of necessity be, equipped 
with a gas preheater or regenerative system in order to get the heats 
out quickly enough. The usual burner for city gas consists of a 
tubular ring with threo or four tangential openings. The gas and the 
air (from a blower) are mixed just before entering the ring. This 
form of burner tends to give a whirling flame about the crucible. 
The burners at some plants are set at the top of the furnace and the 
waste gases taken out by a flue at the bottom, thus giving a down 
draft, but are more commonly placed at the bottom of the furnace. 

Pit-typo furnaces in general are built in a variety of sizes, from 
those taking a No. 18 crucible holding 50 pounds of brass, to a No. 
000 holding 1,800 pounds, the most common size probably being Nos. 
60 to 70 with a capacity of 175 to 200 pounds of metal. In the 
smaller sizes the crucibles of molten metal are lifted by suitable tongs 
and carried to the molds by hand, one to three men being required, ac¬ 
cording to the size of the crucibles; in the larger sizes the crucibles are 
lifted by a traveling crane. 

Many pit furnaces are built by the user, whereas tilting furnaces are 
usually bought from a furnace maker. A few home-made oil or gas 
burners are found, but most burners are bought from dealers or fur¬ 
nace makers. 

A type of pit furnace using a number of crucibles set in one pit and 
heated by fuel oil burning undernatural draft is much used in crucible- 
steel practice. Instead of an atomizing burner being used the oil is 
run into a series of pans (usually two or three), one above the other, 
and drips from the upper ones into those below, burning from the 
surface of the pans and from the cascades of oil from pan to pan.® 

This typo is rarely used for brass and bronze. Data as to the 
experience of one plant using it on red brass are presented in the large 
table, and in the notes following, under reply 198 (p. 114). 

A similar type oi furnace, burning producer gas with regenerative 
heating, is used in crucible-steel practice, 6 and an illustration of one 
for brass or bronze is shown by I horns. c 

o For Illustration and description of a typical furnace of this fonn.se© editorial article in Foundry, voL 
40, Sept., 1912, p. 339. 

t> For drawing, see Stoughton, B, Metallurgy of uron and steel, 1908, p. 89. 

< Ulorns, A. II., Mixed metals, 1890, p. 133. 


/ 




GENERAL TYPES OF FURNACES IN USE. 23 

TILTING FURNACES. 

Tilting furnaces using a crucible to hold the metal are built to use 
oil, or gas, or coke, under forced draft. They resemble those of the pit 
type of oil furnaces that are not wholly or partly put in actual pits. 
The drum that forms the furnace proper is lined with fire brick and is 
placed on trunnions so that it may be tilted by a suitable mechanism. 
The crucible in nearly all of these rests on a refractory crucible block, 
is wedged into the furnace, and has a projecting lip or spout. When 
the metal is hot enough, the furnace is tilted and the metal poured 
into a carrying crucible or a transfer ladle and in this is carried to the 
mold. The melting crucible is usually narrower and deeper than 
those in lift-out (pit) furnaces. 

Most tilting furnaces stand above the ground and, if large, an 
elevated charging platform is provided in order to make the charging 
of the metal less difficult for the furnace tender. Some, however, are 
partly below the floor level, and are tilted by hydraulically operated 
mechanism below the floor. Few til ting-crucible furnaces are built 
with a capacity smaller than 180 pounds and they may have a 
capacity as large as 1,500 pounds, but more commonly hold 300 to 700 
pounds, 375 and 600 pounds being common sizes. 

TILTING, FORCED-DRAFT, COKE FURNACES. 

In tilting, forced-draft, coke furnaces of several makes, the body of 
the furnace is a cylindrical (square in a few) sheet-iron shell, lined 
with fire brick, and Is provided with a closed panlike sheet-iron ash 
pit that makes a tight joint with the body of the furnace when in 
melting position. The body can be raised away from the ash pit and 
tilted to pour the metal. In some forms the ash pit is dropped or 
raised by pneumatic power instead of the body of the furnace being 
raised or lowered. At the bottom of the furnace body arc the grate 
bars, on which rests a refractory crucible block which supports the 
crucible. The crucible, as in most tilting crucible furnaces, is taller 
than those for pit furnaces, with little or no bilge, and has a projecting 
lip for pouring. It is wedged into the furnace at the top. 

Coke is used almost exclusively as fuel. In rare instances, as much 
as 50 per cent of coal is mixed with the coke. No furnaces of this 
type are known to be using coal alone. 

The coke is placed on the grate bars and around the crucible, and 
forced draft is admitted in large volume but at low pressure (usually 
less than 2 ounces) into the ash pit helow the grate. In some forms 
the air is preheated by being passed between the furnace shell and an 
outer casing. 

With this type of furnace there is regularly used a feeder, or pro- 
heater, consisting either of an old crucible with a hole hi the bottom, 


24 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


or of »\ refractory funnel placed directly above the crucible. The 
metal is charged into the feeder and is preheated by the hot waste 
gases before being poked down into the crucible, or the furnace may 
even be run so that the metal melts in the feeder, runs down into the 
crucible, and is there brought to pouring temperature. 

Most of these furnaces are provided with separate hoods leading 
to a stack to carry off the hot gases. Many of the hoods are made 
telescoping so as to come closely down to the top of the furnace when 
running, and may be raised to permit the furnace to be tilted. 

Marteil ° describes a French forced-draft tilting furnace in which 
the air blast, instead of entering beneath the fuel on the grate, is 
admitted through an outer casing around the furnace shell, and is 
forced down on the coke through a number of tubular passages in 
the refractory lining, the tubes being inclined at an angle of about 
45° from the horizontal, so as to blow the air downward. This 
form does not seem to have been used in the United States. 

TILTING, OIL FURNACES. 

A tilting, oil furnace burning any oil, but especially designed for 
kerosene, w r as formerly on the market. The oil dripped by gravity 
ffow r into a cup set below the floor of the furnace. About the cup 
was a shield pierced with holes to admit air under natural draft. 
This furnace is no longer manufactured. 

The common form of tilting, oil furnace uses an atomizing burner. 
This type is similar to the pit, oil furnaces for a single crucible, save 
that it is of larger capacity and on trunnions. There are a dozen or 
more widely used makes of this type, which, aside from minor varia¬ 
tions in the mechanism for tilting or for lifting the cover, differ 
chiefly in the type of burner used, in its location in the furnace, and 
in the size and shape of the combustion chamber. 

OPEN-FLAME, TILTING FURNACES. 

Tilting furnaces without crucible, known as direct-flame or open- 
flame furnaces, consist of an iron or steel shell lined with fire brick, 
carborundum fire sand, or other refractories, and mounted on 
trunnions, so that by tilting the furnaces the metal may be poured 
into ladles. The oil or gas flame plays directly above the metal, 
and the heating comes partly from this and partly by radiation from 
the top of the furnace. 

There are four largely used makes of these furnaces, one with an 
egg-shaped shell mounted horizontally on trunnions, with a hole at 
one end of the shell for the burner and another hole on the side through 
which the products of combustion pass and through which the metal 


a Marteil, V., Alliages et fonder ie de bronie, 1910, p. 77. 






GENERAL TYPES OF FURNACES IN USE. 


25 


is both charged and poured. This form of furnace may consist of 
two of these egg-shaped chambers, each with a burner at one end 
and with its own charging and pouring door, which may he closed 
by a hinged cover, hut with the ends opposite the burners open. 
These chambers are mounted on trunnions, as usual, but with the 
open ends together and the chambers communicating. Charges of 
metal are placed in both furnaces, hut only one burner is lit at a 
time. The cover on the charging door nearer the burner is closed 
and the one farther from it opened. Thus the products of com¬ 
bustion from the chamber nearer the active burner are made to pass 
into the chamber farther from it and out of the farther charging 
hole. Also the waste gases from the first chamber are made to 
preheat the metal in the second chamber. The metal in the first 
chamber is ready to be poured before that in the second is melted, or at 
least before it is up to pouring temperature. After the metal in the 
first chamber has been poured, that chamber is again charged with 
metal, but the second burner is lit instead of the first, so that the 
second chamber containing the preheated metal becomes the furnace 
proper and the first chamber is used as the preheater. The chambers 
thus alternate as melter and preheater throughout the day’s run. 

This arrangement must result in a saving of fuel, but the lining at 
the communicating ends of the chambers (middle of the assembled 
furnace) is subjected to very severe usage by the flame, so that the 
life of the lining at that point is short. Many of the double-chamber 
furnaces, though mounted together, are being used as two distinct 
furnaces, the doors at the charging openings of both chambers being 
left off for the escape of the products of combustion, and both burners 
being used. 

Another type of open-flame furnace is in the shape of a long 
cylinder lying horizontally, the burner and the hole for charging and 
pouring being placed much as in the first type. A third type has a 
spherical lower part and a conical upper part, at the top of which is 
a charging door. Two, or even three, burners project through the 
conical part and direct their flames downward when the furnace is 
tilted into operating position. A projecting spout at the side allows 
the metal to be poured. This type of furnace is built to contain 100 
to 30,000 pounds of metal. The larger sizes are used chiefly for 
making ingot from scrap. 

A fourth type is practically a small oil-fired reverberatory, made 
tilting. The outside of the furnace is approximately rectangular, 
and the melting chamber has an oval hearth on which the molten 
metal lies in a pool a few inches deep and has an arched reverberatory 
roof. One form has a burner entering horizontally just above the 
pouring spout, with a charging door on top of the furnace; in another 
form the charging door is on the front end, just above the pouring 


26 


BRA88-FURNACE PRACTICE IN THE 


UNITED STATES. 


spout, and the burner is on the roof of the furnace, pointing down 
toward the metal. 

In all the open-flame furnaces the metal is directly in contact with 
the furnace lining, no crucible being required. 

The most common sizes of open-flame furnaces are charged with 
500 to 750 pounds of metal at a heat, although thoso taking 1,000 to 
2,500 pounds at a charge are by no means rare. 

REVERBERATORY FURNACES. 

Reverberatory furnaces are chiefly used for melting large quantities 
of metal, though their capacity ranges from one-half to 40 tons. In 
some of the larger sizes the metal is tapped into a long runner leading 
directly to the large mold to be filled, instead of the metal being 
carried in a ladle. In some the metal is dipped out instead of being 
tapped. Although this type is common in iron melting and in copper 
smelting and refining, the brass industry uses it more in reducing to 
ingots, borings, and other scrap than for strictly melting purposes. 
When scrap is being refined into reverberatory ingots, most of the zinc 
is intentionally driven out, the refiner aiming for a product high in 
copper, and buying the scrap merely as copper-bearing material. 

In the navy yards, reverberatory furnaces are used both for refining 
and for melting metal for propellers and other heavy castings. 
Gates, defective castings, etc., too heavy to enter other types of 
furnaces without being cut up can be charged whole into reverber¬ 
atory furnaces. When used for brass and bronze melting this type 
usually takers charges of 1 to 7 tons, and consists of a fire-brick shell, 
rectangular in plan, with a fire-brick or a baked-sand bottom, and 
with a roof arched from side to side and somewhat arched from front 
to back, in order to deflect the flame down on the metal. A camel- 
back roof is often used. They are fired with bituminous coal or 
with oil and though smaller are similar to the air furnaces used for 
melting iron ° and the reverberatories used for smelting copper ores 6 
and for refining copper. Illustrations of a camel-back form for soft 
coal are given by Dean, c Marteil,* * Sexton, e and Hiorns/ When 
these furnaces are fired by soft coal, it is burned on a grate in the 
fire box at the front of the furnace, either natural or forced draft 
being used. When fired by oil the burners are usually at the side, 
and m both cases the products of combustion are led to the stack bv 

a For drawings see Stoughton, B., Metallurgy of iron and steel, 1911, pp. 313, 344. 

6 For drawings, see Mathewson, K. P., Development of the reverl»eratory furnace for smelting copper 
ores: Trans. 8th Int. Cong. App. Chem., vol. 3,1912, p. 113, 
r Dean, W. R., Hints on brass foundry: Metal Ind., vol. 11, 1913, p. 10. 
d Martell, V., ALliages et fonderie de bronze, 1910, p. 93. 

* Sexton, A. II., Alloys, p. 274. 

/ lliorns, A. II., Mixed metals, 1S90, pp. 134, 135. 




GENERAL TYPES OF FURNACES IN USE. 


27 


a flue at the hack. They may be fired by oil burned under natural 
draft, pan system, this type being in use for melting nickel,® or the 
oil may be burned in atomizing burners, which may enter the furnace 
either at the front or the side, two or three burners being commonly 
used on the larger furnaces. Of course when oil is used the fire box 
is omitted. 

Dimensions of reverberatories used for brass and bronze are given 
in the notes following the large table, under Replies 79, 80, 81, 82, 83, 
173, 180, and 202, and data on their performance are presented in 
the table under the same reply numbers. 

Reverberatory furnaces are not much used for charges of less than 
a ton, and hence have not found much use in foundries for ordinary 
melting purposes, most of the plants that could make use of a large 
quantity of molten metal at one time having adopted the open-flam© 
oil furnaces, which are really a tilting type of reverberatory. 

CUPOLA FURNACES. 

The cupola furnace is little used for brass melting, except for large 
emergency repair work in shops having a cupola normally used for 
iron, Mit no other means of melting brass in large quantities, though 
many junk refiners have a small cupola that they use for running 
down very impure material, the ingot thus obtained being usually 
further refined in a reverberatory furnace. In the notes on the large 
table, under Reply 80, figures on a test of cupola melting in running 
down red-brass borings show a coke consumption of 17 pounds per 
hundredweight of metal and a metal loss of 8 to 10 per cent. 

Buchanan 6 gives the fuel consumption on cupola melting as 13 
pounds of coke per hundredweight and gives a metal loss of 7.93 
per cent on bronze made from new metal and consisting of 90 per 
cent of copper and 10 per cent of tin, the tin being melted in the ladle 
and the copper melted in the cupola and tapped into the tin. 

He gives a melting loss of 10.1 per cent on previously alloyed 
bronze of the same composition and states that the quality of the 
metal obtained was poor. lie further states that melting in the 
cupola is the most expensive and uncertain of all melting methods 
practiced in the brass foundry. 

Gresham c characterizes both cupola and reverberatory melting as 
wasteful. 

Cupola melting is generally considered to give a poor quality of 
product. d 

a For description of furnace of this type see editorial article in Brass World, vol. 9, 1913, p. -11. 

b Buchanan, J. F., Practical alloying, 1910, pp. 61, 62. 

c Gresham, W., British manufacturing industries: Brass Founding, 1876, p. 133. 

d Editorial, Casting a large copper ladle: Foundry, vol. 41,1913, p. 543; Parry, W. H., What is brass?: 
Metal Ind., vol. 12,1914, p. 28. 






28 


BRASS-K V ItNACE PRACTICE IN THE UNITED STATES. 


Asiclo from refining, the only known commercial use of cupola 
melting for brass and bronze in this country is among a few small 
foundries making sleigli bells as their chief product. In those plants, 
according to Sperry,® scrap yellow brass, and miscellaneous scrap, 
skimmings, etc, are charged into small furnaces consisting of a tire- 
brick wall with a flue opening into it and leading to a stack, against 
which is placed a sheet-iron casing, approximately in the shape of a 
half cylinder, lined with fire-brick or other refractory. A ladle lined 
with fire clay is put at the bottom of the furnace as a hearth to receive 
the metal. The ladle Is removed at the end of the heat and the 
metal poured from it into the molds. The metal and the charcoal 
fuel, which is used instead of coal or coke because of the detrimental 
effect of sulphur-bearing fuels on metal melted in contact with them, 
arc charged together into the furnace, and the blast from a small 
fan (in earlier days run by water power but now operated by elec¬ 
tricity) is admitted through tuyeres. The furnaces take about 60 
pounds at a charge and turn out a heat an hour. The furnace both 
melts and refines yellow-brass scrap, a practically zinc-free metal 
resulting. Tin is added in the ladle after the heat is over if there was 
not enough in the original scrap. 

No information is available as to fuel consumption or metal losses 
in the charcoal cupolas, but it is certain that practically all the zinc 
in the metal charged is lost. As, in cupola melting, the metal must 
run as drops or line streams into the hearth, passing through the 
path of all the products of combustion, there is every chance for 
volatilization of the zinc; hence the use of a cupola is practically 
confined to the melting of bronze. There is a great chance for metal 
to be retained by the ash in such a furnace. 

Gowland 6 describes the cupola furnace commonly used in Japan, 
with charcoal as fuel, for melting statuary bronzes. 

Horner c describes a forced-draft, tilting, coke furnace, said to be 
used in England, with a preheater or feeder above the melting 
crucible proper. Instead of using the feeder merely as a preheater, 
as is the usual practice, coke is charged into the feeder with the 
metal, and an air blast is led into the feeder through tuyeres, thus 
making a little cupola on top of the regular melting crucible. This 
scheme is not used in the United States. 

SEMIPRODUCER FURNAC ES. 

The gas-generating or semiproducer furnace should be mentioned 
because of the present-day interest in cheap fuel on account of the 
recent considerable increase in the price of fuel oil, and the general 

° 8perry, K. 8., The 1* *11 industry of Kast Hampton: Brass World, vol. 9.1913, p. 3. 

* Oowland, W., The art of working metals in Japan: Jour. Inst. Met. (British), vol. 4,1910, p. 34 . 

* Homer, J., Furnaces for melting brass: Engineering (London), vol. 90,1910, p. 561. 





GENERAL TYPES OF FURNACES IN USE. 


29 


tendency toward an increase in the prices of anthracite coal and 
coke, rather than because of any present commercial use for brass 
melting in this country. 

This type, as applied to brass melting, is only in the development 
stage. The basic principle is that of combining a small gas producer 
with a melting furnace, making gas from soft coal, anthracite coal, 
or coke, and utilizing both the sensible heat of the gas and that pro¬ 
duced by its combustion. Marteil ° illustrates a French tilting 
furnace of this type using petroleum coke. The crucible is supported 
over a bed of fuel but not in contact with it, combustion space for 
gas being provided both below and around the sides of the crucible. 
Air is blown into the fuel bed, but not in quantity sufficient for com¬ 
plete combustion. Another air inlet above the fuel bed and below 
the crucible supplies more air to complete the combustion. The 
waste gases are then led out over the surfaco of the metal in the 
crucible, the final exit opening being in the center of the cover. 

An American patent describes a pit furnace to take a single cru¬ 
cible that rests directly on the coal (the patent does not specify 
whether anthracite or bituminous coal is to be used). Air alone, 
or, preferably, a mixture of air and dry steam, is blown into the 
fuel bed through a casing about the furnace bottom and then through 
a half dozen downward-pointing tubular openings in the refractory 
lining. No separate ports to admit air for combustion of the gas 
produced are provided, all the air entering through the half dozen 
openings and passing through the fuel bed. 

Another design aims to obtain the advantages of cheap bituminous 
coal as a fuel and of hot producer gas by generating hot gas, retarding 
its combustion until it is delivered to the final heating zone, and 
then supplying air for combustion. The nature of the flame is to be 
regulated by controlling the air supply. This form has so far been 
applied chiefly to annealing furnaces, but the makers expect to 
apply it also to brass melting, either in a reverberatory type of furnace, 
or to a number of crucibles in the same melting chamber. The 
design calls for a rocking grate below tho melting chamber which 
will bo suspended above it. Steam is to bo forced through a deep 
bed (probably 18 inches deep) of soft coal on the grate, and the heat 
of the producer gas thus made will serve to warm the bottom of the 
melting chamber. 

The hot gas is then to be led up the sides of the melting chamber, 
supplying some heat to the sides. It is then to be admitted to tho 
melting chamber through ports, and for its combustion, air, in a 
regulated supply, is also to bo admitted at various ports. The gas 
will thus be burned within the melting chamber if crucibles are used, 
or over tho metal if the furnace is of the reverberatory type. 


a Marteil, V., Alliages et fonderie do bronze, 1910, p. 91. 







30 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


A rather similar typo of brass furnace of French design, using hot 
gas from a producer that forms part of the furnace, is illustrated by 
Damour.® 

Suspending the melting chamber over the fire box or producer 
chamber, although doubtless practicable for annealing furnaces, 
would offer some difficulties in a reverberatory of largo capacity. 
With such an arrangement the melting chamber would rest on the 
ground, the fuel would bo burned in a fire box or producer at the 
front or side of the melting chamber, and the gas would be led to the 
melting chamber as before. Discussions and illustrations of brass 
and bronze melting furnaces in general are given by Krom, 6 E. L. 
S. N., c and Horner : d 

FURNACE DATA FROM TIIE LITERATURE. 

Some information as to fuel consumption and loss of metal in melt- 
ing may be gleaned from foundry literature and from catalogues of 
furnace makers, or from their advertisements in the foundry period¬ 
icals. Much of the information in the literature is of little use, 
because few data are available as to the following details: The per¬ 
centage composition of the alloy; whether new metal, ingot, heavy 
scrap, or borings aro used; the size of the crucible; whether the 
figures aro based on a whole day’s run and include the first heat, 
before the furnace has been heated up, or on a single heat with a hot 
furnace; whether the metal was raised to a high temperature for 
light castings, or only to a low one for heavy ones, and other vari¬ 
ables that play a large part in both fuel consumption and metal loss. 

Furnace makers’ statements are usually to be taken as represent¬ 
ing ideal conditions and not as reflecting actual practice, save when 
actual tests by users are reported by the furnace maker. Some data 
obtained from books, periodicals, and catalogues follow. 

NATURAL-DRAFT, PIT, COKE FURNACES. 

The maker of a rival (forced-draft) typo of furnace states that in the 
natural draft, pit, coke furnace with No. 70 crucible the fuel con¬ 
sumption per hundredweight of metal is 70 to 95 pounds, and the 
melting loss on red-brass ingots, 3 to 4 per cent; on red-brass turn¬ 
ings, 4 to 5 per cent; and on yellow brass 5 to 6 per cent. The speed 
is given as three to four heats a day. 

Another maker of a rival furnace states that the melting loss in this 
type on yellow brass, consisting of 87 per cent of heavy scrap and 13 

<* * Damour, E., Industrial furnaces, 1906, p. 99 (trans. by Queneau). 

& Krom, L. J., The development of melting furnaces: Metal Ind., vol. 7, 1909, pp. 2X7, 324, 358, 404, 436, 
vol. 8, 1910, p. 80. 

* E. L. 8. N., Development of English melting furnaces: Metal Ind., vol. 8, 1910, p. 244. 

* Homer, J., Furnaces for melting brass: Engineering (London), vol. 90, 1910, pp. 559, 654, 660, 726; 
Utilization of waste heat from brass furnace: Foundry, vol. 41,1913, p. 113. 




FURNACE DATA FROM THE LITERATURE. 


31 


por cent of chips, is 3.5 per cent; on 100 per cent chips, 8 per cent; 
on 100 per cent heavy scrap, 4.4 per cent; and on alloyed ingot, 2 per 
cent. 

Booth 0 gives the melting loss (alloy not stated) as 3.5 per cent; 
fuel consumption, 62.5 pounds per hundredweight; crucible life (size 
not stated), 20 heats. 

Corse 6 says, “I have obtained from different people figures as to 
the natural-draft coke furnaces varying from 25 to 75 pounds of coke 
per hundredweight. I rather think the average will run between 40 
to 50 pounds. I have seen results as low as 28 and 30.” 

It is stated c that the fuel consumption in this type is 40 to 50 
pounds per hundredweight, and even as low as 25 pounds, but that 
the latter figure is to be taken with a grain of salt. The speed of 
melting is given as 4 to 6 heats in 9 hours, with a No. 70 crucible. 

Wood d gives a loss of 5.4 per cent on red-brass chips and a fuel 
consumption of 66 pounds per hundredweight on yellow-brass chips, 
with coke as fuel, a loss of 5 to 7.6 per cent, with a fuel consumption 
of 63 to 65 pounds per hundredweight, with a No. 200 crucible, and on 
yellow brass, consisting of 93 per cent of new metal and 7 per cent of 
chips, a loss of 2.4 per cent. 

Marteil 6 gives the fuel consumption as 50 pounds per hundred¬ 
weight (alloy and crucible size not given). 

Quigley f gives a loss of 3.25 per cent on melting a composition 
consisting of S8 per cent of copper, 5 per cent of zinc, 4 per cent of tin, 
and 3 per cent of lead. 

Primrose* 7 gives, for 160-pound heats in the natural-draft, pit, 
coke furnaces, melting gun metal, a fuel consumption of 44 pounds 
per hundredweight. 

Clamer and Hering h put the coke consumption in pit furnaces at 
45 to 50 pounds per hundredweight. 

FORCED-DRAFT, PIT, COKE FURNACES. 

Marteil { gives the fuel consumption in forced-draft, pit, coke fur¬ 
naces as 30 to 32.5 pounds per hundredweight. The maker of the 
forced-draft furnace who gave the figures mentioned abovo for the 
natural-draft furnace gives for the forced-draft furnace (forced draft 
of H to 6 ounces crucible No. 70) loss figures of 1 to 1.5 per cent, a 

o Booth, W. II., Liquid fuel and its combustion, 1901, p. 276. 

Corse, W. M., in discussion in Trans. Am. Brass Founder’s Assoc., vol. 5, 1911, p. 40. 
e Editorial, Replies to correspondents under “ Brass-Foundry Difficulties”: Foundry, vol. 40,1912, p. 418. 
<i Wood, R. A., Some results from melting brass chips: Metal Ind., vol. 10,1912, p. 378. 
e Marteil, V., Alliagcs ct fondcrie do bronze, 1910, p. 71. 
t Quigley, W. S., The brass foundry: Metal Ind., vol. 5, p. 358. 

0 Primrose, H. S., A discussion of modern brass founding: Foundry, vol. 90,1912, p. 366. 

A ( lamer, G. II., and llcring, C., The electric furnace for brass melting: Trans. Am. Inst. Metals, vol. 6, 
1912, p. 104. 
i Marteil, V., loc. cit. 




32 


BHASS-FURNACE PRACTICE IN THE UNITED STATES. 


fuel consumption of 38 pounds ]>er hundredweight, and 11 spee<l of 6 
to 8 heats per day. 

Another maker’s figures are 1 per cent loss on heavy scrap and 1.5 
per cent on borings (No. 00 crucible), the speed of melting being 
figured as 45 minutes per heat of red brass and 35 minutes per heat of 
yellow brass. 

V 

NATURAL-DRAFT, PIT, ANTHRACITE FURNACES. 

McPhee ° on material consisting of 75 per cent of heavy alloy and 
25 per cent borings (84 per cent copper, 8 per cent zinc, 5 per cent 
tin, and 3 per cent lead, crucible No. 100) gives a melting loss of 3.5 
to 4 per cent, a fuel consumption of 50 pounds per hundredweight, a 
crucible life of 15 heats, and a melting speed of 2.5 to 3 hours per heat 
in natural-draft, pit, anthracite furnaces. 

Dean 6 puts the fuel consumption in this typo at 65 to 95 pounds 
per hundredweight on red brass. 

Webster c puts the coal consumption on yellow brass at 33 pounds 
per hundredweight. 

Wood d gives on 100 per cent yellow brass chips (No. 70 crucible) a 
coal consumption of 64 pounds per hundredweight and losses of 5 to 
7.6 per cent. On yellow brass, mostly heavy alloyed material, with 6 
per cent chips, ho gives a loss of 2.4 per cent. For brass consisting of 
80 per cent of copper and 20 per cent of zinc, Clamer and Ilering c 
give the fuel consumption as 40 pounds per hundredweight. 

Latlirop / states that when (yellow) brass is remelted (the brass fur¬ 
naces of Connecticut are almost exclusively natural-draft, pit, anthra¬ 
cite furnaces) a loss in weight of 4 to 6 per cent results. 

Reichhelm 9 reports a coal consumption of 60 pounds per hundred¬ 
weight (alloy and size of furnace not given). He states that ho 
believes the furnace mentioned in the report to be as economical as 
any of its kind. 

Bassett* * gives the loss in melting yellow brass as 6 per cent of the 
zinc used (equivalent to 2 per cent of the melt) and the total loss 
between new metal and finished product as 10 per cent of the zinc 
used (or 3.5 per cent of the melt). 

Wood 1 gives 34 pounds per hundredweight as the average fuel 
figure on yellow brass in rolling-mill practice; and for different mills 
using the same make of crucible, but with varying stack draft, a fuel 

« McPhec, H., The oil or crucible furnace: Metal Ind., vol. 10,1912, p. 404. 

t> Dean, W. II., Coal versus by-product coke in the brass foundry: Metal Ind., vol. 8,1910, p. 461. 

t Webster, W. R., in discussion, Trans. Am. Brass Founders’ Assn., vol. 5,1911, p. 40. 

d Wood, R. A., loc. cit. 

* Clamer, Q. II., and Bering, C., loc. cit. 

/ Lathrop, W. 8., The Brass Industry of Connecticut: 1909, p. 11. 

o Reichhelm, E. P., The heating power of fuels: Araer. Mach., vol. 18, 1895, p. 22. 

* Bassett, W. II., Zinc losses: Jour. Ind. Eng. Chem., vol. 4, 1912, p. 164. 

< Wood, R. A., How much coal does it take to melt u pound of brass: Metal Ind., vol. 11, 1913, p. 88. 



FURNACE DATA FROM THE LITERATURE. 33 

consumption per hundredweight, and a crucible life, of (a) 67 pounds, 
25 heats; (6) 50 pounds, 33 heats; (c) 33 pounds, 48 heats. Good 
fuel economy and good crucible life go together, as do poor results 
on each. 

Buchanan® gives a coke consumption of 75 to 83 pounds per 
hundredweight and a melting loss of 0.9 to 1.1 per cent on new 
bronze consisting of 90 per cent of copper and 10 per cent of tin. 

Sexton * 6 gives for this type of furnace a fuel figure of 36 pounds 
per hundredweight (alloy not given) and states that by the use of a 
perforated inverted truncated cone instead of the ordinary grate bars 
the fuel consumption was cut from 107 to 44 pounds per hundred¬ 
weight on gun metal. On red brass he gives a melting loss of 2.3 
per cent. 

Horner c states that in the natural-draft pit furnace 67 pounds of 
coke per hundredweight is a fair average, but later in the same paper 
gives a figure of 50 pounds per hundredweight. 

FORCED-DRAFT, TILTING, COKE FURNACES. 

One maker of forced-draft, tilting, coke furnaces reports that in a 
test of pure copper the average coke consumption per hundredweight 
of metal melted was 27 pounds, some heats being melted with 22 
pounds per hundredweight. lie gives 17 pounds as the figure on 
brass and bronze, and states in a recent advertisement that the life 
of the crucibles is 15 to 30 per cent longer than in pit furnaces. A 
fuel figure previously given by this maker was 12 pounds per hundred¬ 
weight, and he stated in conversation that it had been as low as 6 
pounds per hundredweight on red brass. 

Corse d says that the fuel consumption with this type of furnace 
runs as low as 15 pounds per hundredweight. 

Horner e states that with forced draft, and by the utilization of 
the waste heat, the coke consumption can be reduced to 15 to 25 
pounds per hundredweight. Other figures given are: 14 pounds of 
coke per hundredweight on a 400-pound charge and 23 pounds per 
hundredweight on a 150-pound charge/ 

Horner 0 gives for gun metal (88 per cent copper, 10 per cent tin, 
2 per cent zinc) in an English furnace of this type a fuel consumption 
of 17 to 10 pounds per hundredweight, and in a German furnace, 
also of this type, 25 pounds per hundredweight with a 110-pound 
charge and 15 pounds per hundredweight with a 660-pound charge. 


a Buchanan, J. F., Practical alloying, 1910, p. 62. 

6 Sexton, H., Alloys, pp. 260, 268. 

c Horner, J., Utilizing the waste heat from brass furnaces: Foundry, vol. 41, 1913, p. 113. 
d Corse, W. M., loc. cit. 
t Horner, J., loc. cit. 

; E. L. S. N., Development of English melting furnaces: Metal Ind., vol. 8, 1910, p. 294. 
o Homer, J., Foundry plant and machinery: Engineering (London), vol. 90, 1910, p. 658. 

41712°—Bull. 73—1G-3 






34 


BRAS8-FUBNACR PRACTICE IN THE UNITED STATES. 


Karr* gives the fuel figure at 14.3 pounds per hundredweight. 

The figure given by Hughes 6 of 20 pounds per hundredweight on 
gun metal is included in the large table as Reply 204. 

Marteil c gives a coke consumption of 15 to 20 pounds in GOO to 
220 pound charges in one furnace of this type; in another, 15 pounds 
per hundredweight (220-pound charge melted in 30 minutes); 12.5 
pounds (440-pound charge melted in 50 minutes) and 15 pounds in 
the largest size (6G0-pound charge melted in 1 hour 15 minutes). 
The crucible life is given as 55 to 60 heats. In still another of this 
type ho gives 15 pounds per hundredweight for bronze and 13 pounds 
for brass, and in yet another, 13.2 pounds for gun metal (88 per cent 
copper, 10 per cent tin, 2 per cent zinc). 

The furnace maker mentioned second in the discussion of natural- 
draft, pit, coke furnaces puts the loss in his furnace (a forced-draft, 
tilting, coke type) at 2.8 per cent on yellow brass consisting of 87 
per cent of heavy scrap and 13 per cent of borings; at 7 per cent on 
100 per cent chips; at 2.75 per cent on 100 per cent heavy yellow 
scrap, and 1 per cent on yellow ingot. The crucible (capacity 600 
pounds) Is said to have a life of 35 heats, and one lining a life of 350 
heats. 

The maker of another furnace of this type states that when hard, 
72-hour, Connellsville coke is used, the fuel consumption runs from 
18 to 20 pounds per hundredweight, and that it is not recommended 
that hard coal be used in this furnace. 

Japing and Krause d give 10 to 20 pounds per hundredweight as 
the figures on this type. 

PIT, OIL FURNACES. 

Booth* gives on a 40-pound charge in a pit, oil furnace a fuel con¬ 
sumption of 3 gallons of oil per hundredweight, a melting loss of 1.5 
per cent (alloy not given), and a crucible life of 30 heats. 

Reichhelm^ compares the figure of GO pounds of coal per hundred¬ 
weight, which he reports for a coal furnace, with one of 1.9 gallons 
of naphtha per hundredweight. The naphtha was “converted into 
gas.” There is nothing in his paper to show whether this statement 
refers to true gasification or to mere atomization, and the size of the 
furnace and the composition of the brass melted are not given. 

Clamor and Hering? give the oil consumption per hundredweight 
on bronze as 3.0 to 3.8 gallons and on brass as 1.8 gallons (type of oil 

a Karr, C. P. (In discussion): Trans. Am. Brass Founders’ Assoc., vol. 4, 1910, p. 142. 

b Hughes, O., Nonferrous metals in railway work: Metal Ind., vol. 9, 1911, p. 426; Castings, vol. 9,1911, 
p. 13; Jour. Inst. Met. (British), vol. 6,1911, p. 96. 

c Marteil, V., loc. cit. 

d Japing, E., and Krause, II., Kupfer und Messing, 1912, p. 92. 

t Booth, W. II., Liquid fuel and its combustion, 1904, p. 276. 

/ Heichhelm, E. I*., loc. cit. 

9 Clamor, G. II., and Bering, C., The electric furnace for brass melting: Trans. Am. Inst. Metals (vol. 6), 
)912, p. 104. 





FURNACE DATA FROM THE LITERATURE. 


35 


furnace not given). One maker, for a furnace provided with a burner 
using low-pressure air and high-pressure oil, claimed an oil consump¬ 
tion of 2.96 gallons of oil per hundredweight on alloys running 86 to 
75 per cent copper, and claimed a melt of 220 pounds in a No. 80 
crucible in an hour with a melting loss of 1 per cent and a crucible 
life of 42 heats. A later claim by the same maker was that the time 
of the heat could be reduced to 90 per cent of the above figure, and 
the oil consumption reduced to 1.82 gallons per hundredweight. 

The claim for another furnace of this type is 2 to 2.5 gallons of 
oil per hundredweight, with 1.5 per cent melting loss on red brass. 
Another claim is 3 to 1.75 gallons, and still another puts the oil fig¬ 
ures at 5 to 2 gallons per hundredweight. 

T et another maker claims 2 gallons of oil per hundredweight and 
1 per cent loss on red brass, and quotes a test by a user of his furnace 
that showed an oil consumption of 1.7 gallons per hundredweight 
and a loss of 0.5 to 0.6 per cent on bronze. Another claim (for an 
English furnace) on gun metal is a fuel consumption of 2 gallons per 
hundredweight on a 50-pound charge and of 1 gallon per hundred¬ 
weight on a 500-pound charge. 

Another maker gives figures of 2 gallons per hundredweight and 
10 heats per day for a No. 70 crucible and a molting loss “less than in 
a coke furnace.” Still another claims for a No. 70 crucible a fuel 
figure of 1.75 gallons per hundredweight. A test quoted by a maker 
of this type of furnace on red brass, mixed heavy scrap and borings, 
showed a fuel consumption of 2 gallons of oil per hundredweight 
(air preheated) and a melting loss of 1.4 per cent, with 180-pound 
charges (No. 60 crucible) and one heat per hour. 

The maker of an oil furnace using a low-pressure air burner gives 
the following comparison of his furnace with one using high-pressure 
air, both using a No. 60 crucible and 165-pound charges: Low-pressure 
air—7 heats in 6.2 hours, oil consumption 1.6 gallons per hundred¬ 
weight; high-pressure air—6 heats in 7.3 hours, oil consumption 3.3 
gallons per hundredweight. 

As makers of crucible oil furnaces usually build both pit and tilting 
types, the maker’s claims above given may bo taken to apply to 
either type. A few figures known to cover tilting furnaces are given 
below. The firm that made the natural-draft, tilting, oil (or kero¬ 
sene) furnace when it was on the market stated that one size, of 
165-pound capacity, would melt that quantity of copper in two hours 
from a cold start, successive charges being melted in less than an 
hour, the fuel consumption being 1J gallons of kerosene per hour. 
The crucible was stated to last 50 heats. It was stated that “there 
is no smoko after the combustion chamber has been heated for a 
few minutes.” 


36 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


Sexton 0 gives, for oil consumption in the utomizing-burner type 
of tilting oil furnace, figures varying from 2.4 to 4.5 gallons and a 
loss figuro (alloy not given) of 1.3 per cent. 

Horner,* * on gyn metal, states that 400 to 600 pounds may bo 
melted per hour in this type, with 1.5 per cent loss. 

The following figures are quoted by one maker from a recent tost: 
Xo. 275 crucible; 3,244 pounds of material, consisting of 90 per cent 
of copper, 3 per cent of zinc, and 7 per cent of tin, melted in 6$ hours; 
first four heats each of 711 pounds; fifth heat of 400 pounds; first 
heat took 1 hour 41 minutes and used 2.8 gallons per hundredweight; 
second heat took 1 hour 18 minutes and used 1.8 gallons per hundred¬ 
weight; third hoat took 1 hour 10 minutes and used 1.6 gallons per 
hundredweight; fourth heat took 1 hour 12 minutes and used 1.6 
gallons per hundredweight; fifth heat took 48 minutes and used 2 
gallons per hundredweight; average fuel consumption, 1.95 gallons 
per hundredweight. 

Another furnace makor claims a fuel consumption of 1.75 gallons 
per hundredweight on 400-pound heats. 

McKinnon, c on red brass and gun metal containing 12 per cent of 
borings and melted in a tilting crucible oil furnace, gives a fuel con¬ 
sumption of 3.75 gallons per hundredweight and a gross loss of 4.6 
per cent, which included sucli foundry losses as those in grinding, as 
well as the actual melting loss. 

I^enning d gives figures on the melting of 5,300 pounds of various 
bronzes in 9 hours 20 minutes in a German tilting, oil-fired, crucible 
furnace, using an air pressure of about 7 pounds per square inch and 
taking 660 pounds of metal at a charge. The figures show an oil 
consumption of about 2 gallons per hundredweight and melting losses 
ranging from 0.2 to 1.13 per cent and averaging about 0.7 per cent. 

TILTING, OPEN-FLAME, OIL FURNACES. 

Makers claim that for different sizes of tilting, open-flame, oil 
furnaces with capacities of 450 up to 2,700 pounds the oil con¬ 
sumption is 2 to 1.5 gallons per hundredweight, and for another 
style, with capacities of 330 to 1,770 pounds, that the oil consump¬ 
tion is 1.75 to 1.25 gallons. 

For different furnaces with capacities of 100 to 30,000 pounds 
another maker gives an oil consumption of 2.25 to 1.25 gallons per 
hundredweight and quotes a user as getting 0.5 per cent melting loss 
in this type of furnaco on material consisting of 84 per cent of copper, 
3.5 per cent of zinc, 12.5 per cent of tin, and 0.5 per cent of lead. 

« Sexton, A. H., Alloys, p. 268. 

t> Homer, J., Foundry plant and machinery: Engineering, vol. 90,1910, p. 65R. 

* McKinnon, II. P. (in discussion): Trans. Am. Brass Founders’ Assoc., vol. 5, 1911, p. 41; Met. t hem 
Eng., vol. 9, 1911, p. 364. 

* I^nning, Oelfetirung, System u Buess”: Ciesscrei Zeit., vol. 10,1913, p. 305. 



FURNACE DATA FROM THE LITERATURE. 


37 


A third make is stated to use 2 gallons of oil per hundredweight, 
and other figures are 1J to 2 gallons. 

Smith ° gives 3 gallons of oil per hundredweight as a normal figure 
on material running one-sixth borings (red brass). 

McPhee 6 gives figures showing a melt of 700 pounds of material 
consisting of 80 per cent of copper, 10 per cent of tin, and 10 per cent 
of lead, in 45 minutes, with an oil consumption of 2.15 gallons per 
hundredweight. 

Sexton c gives 2.25 to 1.35 gallons per hundredweight as the oil 
consumption in furnaces of this type. 

Parry d reports the use of 2 gallons of oil per hundredweight of 
ordinary red brass consisting of 86 per cent copper, 5 per cent tin, 

5 per cent zinc, and 4 per cent lead, of which a third or more is charged 
in the form of gates and sprues, some chips also being used. lie gets 

6 heats per day from each furnace of 1,000 pounds capacity, and 
obtains 3,666 heats before relining the furnace. 

Booth, 6 on heavy alloyed red brass in 350 to 500 pound charges, 
gives a fuel consumption of 2.44 gallons per hundredweight and a 
melting loss of 2.25 per cent. 

Quigley/ on an alloy consisting of 88 per cent of copper, 5 per cent 
of zinc, 4 per cent of tin, and 3 per cent of lead (which lost in pit coke 
furnaces 3.25 per cent) gives a loss of 3.18 per cent and a fuel con¬ 
sumption of 1.53 gallons per hundredweight in an open-flame furnace. 
He also gives a figure on bearing metal (40 per cent new metal, rest 
scrap) of 1.62 gallons per hundredweight. 

On high-zinc alloys in the open-flame oil furnace one maker claims 
less than 10 per cent loss on manganese-bronze borings. 

Jones 0 gives gross melting losses on manganese-bronze ingots and 
gates as 4.3 per cent, as compared with 6.1 per cent on the same in a 
pit coke furnace. 

Weeks h gives on yellow brass a net melting loss of 1.3 per cent and 
an oil consumption of 1.8 gallons per hundredweight. 

Reardon,* on an alloy consisting of 73 per cent of copper, 18 per 
cent of zinc, 2 per cent of tin, and 7 per cent of lead, with 46 per cent 
of new metal, no borings, gives figures showing 7 heats of 650 pounds 
each in 6 hours, with a fuel consumption of 2.4 gallons per hundred¬ 
weight and a loss of 1.13 per cent. 

a Smith, J. (in discussion): Tmns. Am. Brass Founders’ Assn., vol. 5,1911, p. 41. 

b McPhee, II., The oil or crucible furnace: Metal Ind., vol. 10,1912, p. 465. 

c Sexton, II., Alloys, p. 277. 

d Parry, W. II., Brass-foundry furnaces: Metal Ind., vol. 11,1913, p. 423. 

t Booth, W. II., Liquid fuel and its combustion, 1909, p. 276. 

/ Quigley, W. S., loc. cit. 

g Jones, J. L., The effect of repeated melting on manganese bronze: Trans. Am. Brass Founders’ Assn., 
vol. 5,1911, p. 128. 

h Weeks, C. A., Melting nonferrous metals in an electric furnace: Met. Chem. Eng., vol. 9,1911, p. 363. 

i Reardon, W. J., The manufacture of high-copper castings: Metal Ind., vol. 8, 1910, p. 212. 





38 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


Jones® gives the following average melting losses per hundred¬ 
weight in open-flamo furnaces: Copper, 1 percent; red brass, 1 J per 
cent; yellow brass, 2 percent; copper turnings, 1$ percent; red- 
brass turnings, 2 per cent; yellow-brass turnings, 3 per cent; ingot 
aluminum, 0.5 per cent. 

Hansen 6 gives figures for three types of open-flame furnaces. The 
alloy consisted of 81 per cent of copper, 1G.5 per cent of zinc, 1.5 per 
cent of tin, and 1 per cent of lead, 50 per cent being new metal, 30 per 
cent heavy alloyed scrap, and 20 per cent borings. Under ordinary 
running conditions the figures were: Furnace A—1,000-pound charge, 
88 minutes per heat, 3.5 gallons of oil per hundredweight, 5.8 per cent 
loss; furnace B 750-pound charge, 71 minutes per heat, 2 gallons 
per hundredweight, 2 per cent loss; furnace C- 750-pound charge, 
85 minutes per heat, 2 gallons per hundredweight, 3 per cent loss. 
Under careful test conditions furnace A, on 1,000-pound charges, 
averaged 43 minutes per heat, 2 gallons of oil per hundredweight, and 
2.3 per cent loss; furnace B, on 700-pound charges, averaged 64 
minutes per heat, 1.8 gallons of oil per hundredweight, and 1.8 per 
cent loss. 

Furnace A, in electrical energy for the motor running the air blast 
for the burner, used 1.14 kilowatt-hours per hundredweight of metal 
melted, whereas this furnace under test conditions and all the tests 
on furnaces B and C averaged about 0.65 kilowatt-hour for the blast 
used in melting 1 hundredweight. 

REVERBERATORY, COAL FURNACES. 

Marteil,* * for a 4-ton reverberatory, gives a coal consumption of 30 
to 35 pounds per hundredweight and a melting loss of 6 to 8 per cent 
(alloy not given). 

Buchanan d gives a coal consumption of 80 pounds per hundred¬ 
weight and a melting loss of 3.6 per cent on an alloy consisting of 90 
per cent of copper and 10 per cent of tin from new metals. 

Sexton * gives a figure of 50 pounds of coal per hundredweight, and 
states that in a furnace taking 5 tons at a heat tliis Is reduced to 33 
pounds (alloy not given). 

Iliorns / states that the reverberatory Is used chiefly for melting 
yellow metal, but that the loss of zinc is so great that most (British) 
foundries have gone back to crucible melting. 

Primrose,* describing English practice, states that for small gun- 
metal work the pit furnace is suitable where the output is not large, 

a Jones, J. K., Shrinkage: Metal Ind., vol. 11,1913, p. 267. 

Hansen, C. A., Electric melting of copper and brass: Trans. Am. Inst. Metals, vol. 6,1912, p. 116. 

t Marteil, V., Alliages et fonderie de bronre, 1910, p. 94. 

d Buchanan, J. K., Practical alloying, 1910, p. 62. 

• Sexton, A. II., Alloys, p. 274. 

/ Iliorns, A. II., Mixed metals, 1890, p. 127. 

9 Primrose, II. S., A discussion of modem brass founding: Foundry, vol. 90,1912, p. 363 et seq. 





FURNACE DATA FROM THE LITERATURE. 


39 


but that for larger work a reverberatory, or air furnace, of suitable 
size is advantageous. lie cites a test on a heat of 14,000 pounds of 
gun metal, consisting of 30 per cent of new metal, 15 per cent of 
borings, and 55 per cent of scrap, which was melted in 6£ hours, 26 
pounds of splint coal per hundredweight being used, but states that 
20 pounds per hundredweight is the usual fuel consumption. The 
calculated analysis was 87 per cent copper, 9.7 per cent tin, 2.7 per 
cent zinc, and 0.6 per cent lead. The actual analysis showed 87.9 
per cent copper, 9.5 per cent tin, 2.0 per cent zinc, and 0.6 per cent 
lead, a composition that would mean a melting loss of about 1 per 
cent. 

Japing and Krause a give a fuel consumption of 25 to 50 pounds 
per hundredweight and a melting loss of 6 to 12 percent, seemingly 
for bronze. 

GAS FURNACES. 

The following figures for gas-final furnaces are found in the litera¬ 
ture. One maker of tilting-crucible furnaces, for a 275-pound charge, 
gives a consumption of natural gas of 225 cubic feet per hundred¬ 
weight of metal. In the open-flame, natural-gas, tilting furnace, 
Reardon 6 gives the following figures for an alloy consisting of 73 
per cent of copper, 18 per cent of zinc, 2 per cent of tin, and 7 per 
cent of lead, with 46 per cent of new metal and no borings; 7 heats of 
650 pounds each were made in 10 hours, with a gas consumption of 
144 cubic feet per hundredweight, and a melting loss of 2.7 per cent. 

The makers claim for ono type of open-flame natural-gas furnace 
a fuel consumption of 220 to 330 cubic feet per hundredweight, and 
for another a fuel consumption of 245 to 280 cubic feet per hundred¬ 
weight. Another furnace maker gives 186 to 230 cubic feet of nat¬ 
ural gas, or 278 to 416 cubic feet of city gas per hundredweight. Still 
another says, in a recent advertisement: “Our fuel-oil furnace has 
been equipped with a new burner for gas, which burns either natural 
or artificial gas. The results of the tests show that gas has coal or 
coke beaten, although it does not beat fuel oil in cost of operation.” 

The loss in refining borings in an 18,000-pound natural-gas rever¬ 
beratory furnace is given as 1.4 to 2.8 per cent. 0 

No figures on fuel consumption in gas-fired reverberatory brass 
furnaces are available. Johnson d states that in the most improved 
open-hearth steel furnace, 500 cubic feet of natural gas yielding 1,045 
British thermal units per cubic foot and under an 8-ounce pressure is 
used in melting a ton of steel, or 250 cubic feet per hundredweight. 
The gas consumption on brass should be considerably less. 

a Japing, E., and Krause, II., Kupfer und messing, 1912, p. SG. 
t> Reardon, W. J., loc. cit. 
c Anonymous, Foundry, vol. 91,1913, p. 129. 

d Johnson, N., Use of natural gas in the manufacture of open-hearth steel: 8th Int. Cong. App. Chem. 
1912, vol. 25, p. 6X5. 






40 


BKASS>FURNACE rttACTICE IN THE UNITED STATES. 


Campbell ° states that city gas lias b(«n substituted for coke in 
inciting gold in the British mint, a crucible of double the capacity of 
the one formerly used in the coke furnaces being employed. The 
fuel cost was 41 pence per hundredweight with gas, as compared with 
7 pence with coke (actual fuel consumption not given), and the metal 
losses have decreased. The crucibles last 18 heats, as compared with 
12 heats for the smaller crucibles in the coke furnaces. The gas is 
burned in a burner taking air under a pressure of 2 pounds per 
square inch and gas under a pressure of about 2 ounces per 
square inch. Campbell states that at the mint oil furnaces that used 
burners taking air under a pressure of 2 to 2.5 pounds per square 
inch have been tried. The oil was more economical than coke, but 
the furnaces were too noisy. 

One furnace maker claims a fuel consumption of 350 cubic feet of 
city gas per hundredweight of hard brass melted, the gas yielding 050 
British thermal units per cubic foot. 

DETAILED RESULTS OF INVESTIGATION. 

EXPLANATION OF TABULATION OF REPLIES. 

In order to facilitate comparison of the performances of different 
furnaces of the same type under approximately like conditions, the 
data obtained in reply to the list of questions relative to brass-melting 
practice have been compiled in one large table with 39 subdivisions. 
It should be remembered, however, that in no two plants are condi¬ 
tions exactly alike, so that no one set of figures can be considered as 
exactly comparable with any other. In comparing any two figures 
in one column for any two replies, all the data tabulated, as well as 
the notes on the reply numbers following the tables, should bo taken 
into account. One groat variable, of which no account can be taken 
because measurements of the temperature of the metal are rare, is 
the temperature to which the metal is heated before leaving the fur¬ 
nace. Another variable that exerts a vast influence is promptness of 
pouring—whether the metal is taken from the furnace just as soon 
as it is ready to be poured, or whether it is allowed to remain (“soak”) 
in the furnace after it is ready. * Still another variable is the volume 
of air and products of combustion passing tlirough the furnace in a 
given time. The draft in a natural-draft furnace is seldom known, 
and varies from day to day. This variation of course affects fuel 
consumption and speed of melting, as well as loss of metal. 

Information that could not be readily tabulated, but throwing 
light on the conditions under which the furnace is used, has been 
given in the notes following the table. 


a Campbell, J. F., Forty-first Annual Report of the Deputy Master and Comptroller of the (llritish) 
Mint, 1911, p. 31; Forty-second Annual Report, 1912, p. 35. 




DETAILED RESULTS OF INVESTIGATION. 


41 


In the table for each fuel a subdivision is made for each of the 
following points: Whether an alloy high or low in zinc is produced; 
whether a furnace is used under natural draft or forced draft; whether 
tho furnace is pit, tilting, or reverberator}"; whether the furnace is 
round or square; whether one crucible, several, or none is used; and 
whether an oil burner works under high or low oil or air pressure. 
Ten per cent of zinc has been arbitrarily taken as the dividing line 
between alloys of low and high zinc content, and an air pressure of 2 
pounds per square inch at the burner has been taken as the dividing 
hue between high and low air pressure oil burners. 

The items of the investigation are given in the vertical columns 
and are numbered. A full explanation of each item is given in tho 
following paragraphs: 

Item 1. Reply No. —This item gives the consecutive number as¬ 
signed to replies as received. 

Item 2. Nature of plant. —According to their nature, plants have 
been divided into jobbing foundries (those making castings and per¬ 
haps doing machine work, but not putting out a finished product 
ready for final consumption—designated “Job” in table); manufac¬ 
turing plants (those making castings that go into a finished product 
made by tho same plants—designated “Mfg.” in table); rolling mills 
(“Roll.”), and refining plants (“Ref.”). A refining plant melts bor¬ 
ings and other scrap into ingots, and may be operated by a firm with 
that as its main business, or tho plant may be a department of a 
manufacturing plant. 

Item 2. Height or shape of furnace. —This item gives inside height 
in inches of the main chamber. In open-flame furnaces tliis item 
gives the furnace shape. 

Item 4- Diameter or inside length of furnace. —This item gives the 
inside diameter of the furnace, if round, or the inside length of a side, 
if square. 

Rem 5. Fuel and air supply. —Tliis item gives grade, size or spe¬ 
cific gravity, analysis; and heat units of fuel, stack draft in inches of 
water or natural draft, pressure in pounds or ounces per square inch 
of air in the fire box or ash pit of forced-draft furnaces, and of air, 
oil, or gas at tho burner for oil or gas burners. 

Rem 6. Analysis of charge. —This item shows the percentage of 
copper, zinc, tin, and lead totheclosesthalf of a percent. Inmany cases 
the figures reported in other columns are for all alloys melted, whereas 
tho analysis given is for the alloy most used. When such cases are 
known, mention thereof is made in the notes. The following abbrevia¬ 
tions are used: R. B. for red brass, approximately 85 per cent copper, 
5 per cent zinc, 5 per cent tin, and 5 per cent lead; Y. B. for yellow 
brass, approximately 6G per cent copper and 34 per cent zinc, with 


42 


BEASS'FURNACE PRACTICE IN THE UNITED STATES. 


or without a little lead; Bz. for bronze, approximately DO per tent 
copper and 10 per cent tin; Mn. Bz. for manganese bronze, approxi¬ 
mately 56 per cent copper and 41 to 42 per cent zinc, with some iron, 
tin, aluminum, and manganese; G. S. for German silver, approxi¬ 
mately 62 per cent copper, 23 per cent zinc, and 15 per cent nickel; 
Ph. Bz. for leaded bearing bronze of say 78 per cent copper, 7 per 
cent tin, and 15 per cent lead. The abbreviations are used only 
when no more definite information as to the composition of the alloy 
is stated. 

Item 7. Composition of charge. —This item has been divided into 
now metal, heavy alloy, such as “composition ingot,’’ gat<*s, sprues, 
defective castings, and all heavy scrap; and light alloy, such as chips, 
borings, turnings, and small pieces of thin punchings from sheets. 

Item S. Crucible maker's No. —Standard sizes of crucibles usually 
hold nearly 3 pounds of molten brass per number; that is, a No. 60 
crucible, when new and full, holds about 180 pounds. Crucibles 
from various makers vary somewhat in capacity and in form. The 
standard crucible for tilting furnaces is tall. Special crucibles (usually 
of taller form than the standard) are denoted by “sp.” 

Item 9. Weight of charge. —In open-flame or reverberatory furnaces 
Item 9 is rated capacity in pounds. This item is for a single heat. 
In double-chamber open-flame furnaces, used as such, both chambers 
are regarded as a single furnace. If used separately, each chamber 
is regarded as a furnace. 

Item 10. Heats per day. —This item refers to an individual furnace. 

Item 11. Hours per day. —This item refers to the furnace and not 
necessarily to the whole shop, as in natural-draft pit furnaces the 
fires are sometimes lighted early by the night watchman, and in 
other cases the furnaces may not run as long as the shop. The hours 
given, in general, are to be taken as not counting the noon hour or 
half hour. In natural-draft pit furnaces melting usually goes on 
during this time as fast as during regular working hours. In tilting 
furnaces, the furnaces are usually either empty over noon or else 
the oil or gas flame (or blast in tilting coke furnaces) is lowered. 

Item 12. Hours per heat. —This item is calculated from items 10 
and 11. 

Item IS. Furnaces per tender. —This item is intended to count 
furnace helpers as tenders, and has seemingly been generally so 
reported. Possibly in some cases the helper’s work has not been 
included. The basis for this item, and the one depending on it, 
item 17, metal per tender per hour, will vary in different plants, as 
in some plants the furnace tender sorts scrap, weighs metal, fires and 
charges the furnaces, pulls the pot, and may even help carry it to 
the mold, whereas in others the charges are weighed out from the 




DETAILED RESULTS OF INVESTIGATION. 


43 


stock room and brought to the tender in tote boxes, and in others the 
pots are pulled and poured by a separate gang of men. In the case 
of rolling mills items 13 and 17 refer to each man of the gang, which 
usually consists of a caster, his helper, and a mold man. Hence the 
rolling-mill production per man per hour is figured on a different 
basis from that in other shops because of the impossibility of separat¬ 
ing the duties of the individuals in the gang. 

Item, 14. Metal per furnace per day. —This item is figured from the 
weight of the charge and the number of heats. 

Item 15. Metal per furnace per hour. —This item is figured from 
items 14 and 1G. 

Item 16. Time per hundredweight of metal melted. —This item is 
the reciprocal of item 15. 

Item 17. Metal per tender per hour. —This item is explained under 
item 13. 

Item 18. Life of crucibles. —This item refers to the number of 
heats obtained before the crucible is discarded. Obviously, no figures 
appear for open-flame or reverberatory furnaces. 

Item 19. Life of lining. —This item refers to large repairs, when 
practically a whole new lining is put in, not to patching or minor 
repairs, unless so stated. 

Item 20. Fuel consumption per hundredweight of metal melted .— 
The figures for this item should be read w r ith constant reference to 
the figures representing the analysis and composition of the charge 
and to the notes following the table. 

Item 21. Gross melting loss. —The questions were intended to 
bring out merely furnace losses, but the figures in practically all 
replies, save those marked “special” under item 25, are on total 
losses and represent the difference between metal charged into the 
furnaco and that obtained as castings, gates, and sprues. Thus 
they include melting losses proper (oxidation and volatilization and 
loss in skimming and by spilling into ashes) and also metal lost by 
being spilled into shot in pouring, losses in grinding the castings, 
metal stolen, and any other foundry losses. 

Item 22. Net melting loss. —This item represents the gross loss, 
less the recovery from skimmings, spillings, ashes, or any other 
recovery on the gross loss. 

Item 23. See notes on page 70.—Tho notes following the table 
give the comments made by the communicating firms as to the value 
of different types of furnace they have used, or on special conditions 
that exist in their plant. If such a note is given for any reply number, 
it should be read in connection with the tabulated figures, in order to 
make more clear any special variables that may affect tho results 
presented in tho table. 


44 


brass-fuhnace practice in the united states. 


Item 24. Conditions of test , average or special- When “special” 
appears in this column, it means that the data, at least the find- 
consumption and metal-loss figures, are based on special tests, and 
not on running conditions. In other cases tho data are based either 
on foundry records of average running conditions, or on estimates 
of such conditions, and are then designated “average.” 

GENERAL COMMENTS. 

A blank under any item means that no data were supplied on that 
point. If certain conditions greatly affect any result tabulated, 
reference (denoted by f) is made to the notes following tho table. 
A question mark following a result means that its accuracy is ex¬ 
tremely doubtful and that the result could not be satisfactorily 
verified. 

The notes following the table generally give tho exact words of the 
reply received from a plant, though in some cases the reply has been 
paraphrased slightly for brevity. Other replies constitute informa¬ 
tion given in conversation on a visit to the plant. Any comments 
by tho writer of this bulletin are in brackets. The notes do not 
necessarily represent the ideas of the writer. 

Different replies on the same type of furnace usually show a wide 
variation of opinion, so that many of the replies are mutually con¬ 
tradictory. In order to show this variation, and the different sets 
of conditions existing in different plants that lead to such varying 
results, and to so many different points of view, as well as for the 
intrinsic information in them, tho notes are given more fully than 
would have been justified had it not been important tobringout forcibly 
the fact that such differences of opinion and of conditions do exist. 








































































46 


BRASS-FURNACE PRACTICE IN TFIE UNITED STATES 


Detail* of braju-mslting j tract ice in various tyjxt 


[• designates estimated results rather than results leased on averuge running condition*; 

1. HOUND, l’IT, NATURAL-DRAFT, COKE 


Reply No. 

Nature of plant. 

Height or shape of furnace. 

f 

1 

9 . 

2 £ 

M 

s* 

r 

Fuel and air supply. 

Analysis of 
charge. 

ComtKwllion of 
cWrge. 

Crucible maker's No. 

_ 

& 

o 

XL 

S 

• 

if 

9 

O 

• 

a 

N 

a 

□ 

0Q 

.a 

ft. 

New metal. 

Heavy alloy. 

• 

3 

1 

«) 

m 

3 

4 

& 

6 

m 

1 

8 

9 



In 

In. 


Pet. 

Pet. 

Pet. 

Pet. 

Pet. 

Pet. 

Pet. 


Lbs. 

2 

Mfe 



72-hour Connellsville 

R. It. 







100 

2.50 





coke; 12,650 B. t. u.; 














volatile matter, 0.32; 














carbon, 86.6; ash, 13.1; 














sulphur, 1.0. 










7 

Job. 



72-hour Connellsville 

S3 

7 

4 

6 

Some. 

Mostly. 

None. 

80 

200 





coke. 









8 





85 

5 

5 

5 

75 

25 


80 

225 

9 

Mfg. 

36 

17 

By-product; 13,4 'jOO B. t. 

89 

2 

7 

2 

75 

25 

Some. 

70 

187 





u.; draft, 0.17 inch of 














water. 










14 

Ref. 

42 

27 

Coarse, 72-hour Connells- 

83 

7 

4 

6 



inn 

250 

660 



ville coke; volatile 














matter and moisture, 














1.5; carbon, 85.5; ash, 














12; sulphur, 1.0 to 1.7. 










16 

Mfg. 

33 

15$ 

70-hnur ConnelLsville 

R. It. 






None. 

40 

120 


coke. 










IS 

Job. 

34) 


72-hour Connellsville egg. 

R. B. 






Much. 

90,80 

2.50, 200 

34 

Mfg. 

34 

.... 

17 

Connellsville.. 

85 

5 

5 

5 




70 

200 

35 

..do.. 

36 

17 

10.8 per cent ash; 0.50 

It. 13. 







50 

150 



per cent sulphur. 










51 

..do.. 

• • • • 

14 

Crushed; 13 per cen t ash; 

f85 

6 

6 

3 

25 

75 


IS 

55 





1 per cent sulphur. 










B 


24 

18 


It. B. 







(O) 

<200 

64 

Job . 

30 

18 

Crushed Connellsville 

88 

8 

3 

4 

10 

20 

70 

00.80 

170 





large stove. 










64 

..do.. 

30 

20 


88 

8 

3 

4 

10 

20 

70 

100 

275 

67 

Mfg. 

28 

18 

70-hour Connellsville _ 

80 

10 

- • • • 

10 

50 

Some. 

Some. 

40. .V) 

<140 

75 

. .do.. 

27 

15$ 

Egg . 

83 

4 

ltal. 

50 



.50 

1.50 

76 

..do.. 

30 

18 

48diourConnellsville. ... 

85 

5 

5 

5 

50 

50 


60 

180 

77 





85 

5 

5 

5 

25 

.50 

2.5 

60 

ISO 

82 

Mfg. 

44 

20 

Connellsville; ash, 10per 

80 

4 

8 

8 

70 

30 


70 

200 





cent. 










82 

. .do. . 

48 

26 

.do.: . 

80 

4 

8 

8 

70 

30 


125 

310 

97 

.. do. . 



48-hour . 

R. B. 




30 

55 

15 

60,80 


101 

..do.. 

39 

20 

Connellsville . 

80 

10 

5 

5 




( 0 ) 


113 

Job.. 

30 

20 

48-hour Connellsville_ 

84 

8 

2 

6 

35 

25 

40 

70 

190 

114 

Mfg 




R. It. 







50 

125 

}. 

119 

..do.. 

25 

18 

72-hour Connellsville egg. 

R.B. 







140,60, 
\ 80 

125 

Job.. 

25 

18 

.do. 

R.B. 








110 

126 

Mfg. 

30 

19 

Bv-product. 

85 

6 

4 

5 

35 

Some. 

Some. 

60.70 

152 

1 ;•.! 



22 

72-hour. 

91 

2 

7 


.50 

45 

5 

on mi 

135 

133 

Job.. 

32 

17 

Connellsville. 

R.B. 




50 

30 

20 

45 

130 

142 

Mfg. 

33 

24 


83 

10 

3$ 

3$ 




70 

200 

148 

Job.. 

30 

16 


R.B. 


75 

25 

Some. 

20 

50 

153 

Mfg. 

36 

19 


88 

2 

9 

1 

61 

26 

13 

70 

180 

161 

Job.. 

36 

19 

72-hour.. . 

80 

8 

7 

5 

15 

85 


70 

200 

162 

Mfg. 

34 

17 


86 

3 

11 


40 

40 

20 

2.5-35 

•51 

163 

.. do.. 

33 

20 

.do . 

80 


10 

io 




1 100 

340 

168 


32 

20 


R.B. 





None. 

25,30 

50 

177 

Mfg. 

36 

18 

72-hour . 

77 

5$ 

6$ 

11 

55 

20 

25 

45 

135 

182 

..do.. 

60 

24 

By-product; 12,765 B. t. 

R.B. 




33 


67 

100-175 

< 500 





it.’; moisture and vola- 








H 





tile matter, 14; ash. 














14.4; carbon, 71.6. 



• 








<* See also figures for a special test described in the notes following this table, under the reply number 
for these figures. 
t> Patched every 70 heata. 
c I.esB than 4.2. See notes on reply 9. 














































































































DETAILED RESULTS OF INVESTIGATION 


47 


offurnaces and with various fuels. 

t indicates that tho notes on the reply number affect significance of figures so designated., 
FURNACES MELTING LOW-ZINC ALLOYS. 


Speed of melting. 


X 

cl 

T3 

u 

e-* 

2 

03 

© 

Hi 

Hours per day. 

1 

Hours per heat. 

10 

11 

12 

4 

10 

2.5 

5 

9 

1.8 

3 

10 

3.3 

' 4 

11 

2.7 

3 

11 

3. G 


8 

1.3 

t2 

t7 

3.5 

f3-6 

12 

2-4 

3 

8 

2.7 

4J 

9 

2 

2 

9 

4.5 

4 

9 

2.2 

3 

9 

3 

5 

9 

1.8 

4 

9 

2.2 

2 

8 

4 

5 

9 

1.8 

2 

6 

3 

2 

6J 

3.2 

4 

121 

3.1 


8 


4 

11 

2.7 

2 

9 

4 

5 

10 


2 

9 

4.5 

4 

9.5 

2.4 

4 

10 

2.5 

4 

9.5 

2.4 

4 

y 

2.2 

5 

10 

2 

5 

9 

1.8 

4 

9.5 

2.4 

7 

10 

1.4 

G 

11 

1.9 

3 

9 

3 

3 

9 

3 

4 

10 

2.5 


1 

© 

© 

c 

O 

7Z 

1 • 

- * 

© 


B 

& • 

L • 

— § 

CO © 
2^ 


kn 2 

C3 

- & 


E 

a 

C3 


© 

© 

Pt-I 

s 


13 

14 

15 


Lbs. 

Lbs. 

3 

1,000 

100 

5 

1,000 

111 

5 

775 

78 

4 

748 

G8 

2 

1,974 

180 

2! 

720 

90 

4 

500-400 

71-57 

6 

/ 600- 
\ 1,200 

\ 50-100 

G 

450 

56 

(/) 

250 

28 

3 

400 

44 

5 

680 

75 

5 

825 

92 

4 

700 

77 

10 

GOt) 

66 

6 

360 

45 

5 

900 

100 

6 

400 

70 

4 

620 

95 

3 

1,350 

195 

4 

760 

70 

10 

250 

28 

3 



(/) 

220 

25 

5 

710 

75 

6 

510 

54 

5 

520 

55 

10 

800 

89 

6 

250 

25 


900 

100 

3 

800 

84 


360 

36 

2 

2,040 

185 

4 

150 

17 

6 

405 

45 

4 

1,500 

150 


Fuel consumpt ion per cwt. 

of metal melted. 

Melting 

loss. 

Remarks. 

Gross. 

Net. 

See notes on 

page — 

Conditions of test, 

average or special. 

20 

21 

22 

23 

24 

Lbs. 





coke. 

Pet. 

Pet. 



50 


3.4 

70 

Average.o 

25-30 


3.0 

73 

Do. 



2.3 

73 

Special. 

37 

( c ) 


74 

Average. 

30 

3.0 

2.3 

74 

Special. 

*55 

3.0 

*0.5-0.6 

75 

Average.!* 

tw 

3.4 


i t 

Average. 

1 36 



80 

Do. 

56 




Do. 

90 

*8 

*3 

82 

Do. 


*3 


83 

Do. 

. 

h 50 


*3 

84 

Do. 

h 50 


*3 

84 

Do. 

f50 

*3 

*2.3 

. 84 

Do. 

. 

*5-4 

*3 

86 

Do. 

) *60 


*2.5 

M 

Do. 

*33 

*5 

*3 

86 

Do. 

60 


2 

92 

Do. 

45 


2 

92 

Do. 

(*) 

3 

2.8 

97 

Do. 


4-2.8 

3-1.7 

98 

Do. 

) 40 


2 

100 

Do. 

40 


*3 

100 

Do. 


*6-2 

*3 

101 

Do. 

i *80 


*5 


Do. 

) 78 


2.2 

102 

Do. 

i 

*2 



Do. 

) 58 




Do. 

i 50 

*2 


103 

Do. 

) 60 

5-2 

*2 


Do. 

1 .... 


3.3 


Do. 

) 33 

3 

2 


Do. 

i 60 

(t) 

3 

lOo 

Do. 

) 20 

4 

l. 15-1. S 

10C 

Do. 

) f58 

4 

2.5 

107 

Do. 

) 52 

2.1 

1.5 

10J 

Special. 

) 50 

6.7 

5 


Average. 




8-8 

© 

s 


1(5 


Hrs. 

1.4 


0.9 

1.3 

1.3 


0.G 


1.1 

1.4- 

1.8 


© 


3 
t- O 

iz 

- J? 


17 


Lbs 

300 


555 

38S 

544 


3t.o 


225 

289- 

228 


© 

5 

o 

W-. 

o 

o 


bo 

c 


o 

£ 


18 


19 


Heats. Jits. 

t!8. 


30 

30 

27 


flS 


1,200 


( ft ) 


( d ) 


25 900 


480 


2 

/ 300- 
\ 600 

| 19-30 

/ 600- 
11,200 

1.7 

336 

12-15 

470 

3.9 


34 

700 

2.2 

132 

15-20 

300 

1.3 

375 

18-20 

300 

1.1 

460 

1S-20 

300 

1.3 

308 

« 22 


1.5 

660 

25-30 

600 

2.2 

270 

22 

360 

1.0 

500 

26 

750 

1.5 

420 

18 

400 

1.1 

380 

12 

400 

0.5 

588 

23-28 

U) 



45 


1.5 

280 

23 

489 

3.6 

280 

19 

j 600 



30-50 

(*) 

4 



300 

1.4 

375 

36 

750 

1.9 

324 

25 

300 

1.8 

275 

30 

600 

1. 1 

890 

IS 

400 

4 

150 

25-35 

300 

1.0 


26 

1,500 

1.2 

252 

24 

600 

3 


20-30 

fl.550 

0.5 

370 

15-20 

600 

6 

50 

35 

150 

2.2 

270 

19 

900 

0.7 

600 

25-30 

400 


d Patched every ISO heats. 
« Average. 

/ Molder. 


<7 “Up to 100.” 
h About. 

i patched every 50 heats. 


i Patched every 00 heats. 
k Patched every 100 heats. 
i Special crucible. 

























































































































48 


B HASS- P UR N ACE PRACTICE IN THE UNITED STATES 


Details of brass-melting practice in various tyjxs 
(♦ Deslgiaites estimated reaulta rather than results hated on average running conditions; 

l. HOUND, PIT, NATURAL-DRAFT, CORK 


• 

• 






"1 










Analysis or 

lll.lfiV. 

i cmposu ton oi 
charge. 

• 

o 


Nature of plant. 

o 

s. 

% 

S 

Cl 

Diameter or inside 
of furnace. 

Fuel and air supply. 

p 

O 

Zn. 

d 

0Q 

• 

New metal. 

Heavy alloy. 

Light alloy. 

Crucible maker's N 

| 

4 

w 

O 

• 

if 

4> 

m 

3 

4 

5 

6 

m 

* 

8 

9 


In. 

36 

In. 


Pet. 

tR.R. 

Pet. 

Pet. 

Pet. 

Pet. 

Pet. 

Pet. 

40-100 

Lb». 

alll 

Mfg. 

Job. 

Mfg. 

..do.. 

..do.. 

..do.. 

35 

36 

32 

32 

32 


Volatile matter,2.2; ash, 
10.2; carbon, 87.2; sul¬ 
phur, 0.4. 

It. B 




25 

75 


40-100 

a 75 

20 

16 
i § 

88 

R.B. 

4 

5J 

24 


70 

Coal; 9.2 per cent ash; 
13,000 B. t. u.; coke, 
11.6 per cent ash; 0.9 
per cent sulphur. 


70 

30 


40 

120 

It . R 




70 

30 


60 

180 

20 

It.B. 




70 

30 


80 

240 

88 

2 

10 



120 

250 

Roll 

42 

32 

’it 

16 

48-hour 

95 


d 5 




None. 


175 

Mfg. 

..do.. 


♦R.B. 





8(J 

40 

200 

33 

17 


tit.II. 




10 

80 

10 

1 

..do.. 

33 

19 


flt.B. 




10 

80 

10 

010,70, 

\ i rwk 

\ a 138 






\ 100 

1 


o 

V. 


a. 

ss 


183 

1M 


186 

188 

1S8 

1SS 

lf>7 

2in 

204 

206 

206 


2. SQUARE, PIT, NATURAL-DRAFT, COKE 


32 

Mfg. 

32 

» 

33 

..do.. 

40 

18 

38 

48 

..do.. 

.lull 

42 

24 

65 

..do.. 

38 

19 

70 

Ref. 


21 

72 

Mfg. 

36 

24 

74 

..do.. 

42 

IS 

74 

..do.. 

42 

22 

74 

..do.. 

48 

24 

87 

Job . 

48 

20 

87 

..do.. 

60 

24 

1.59 

..do.. 

30 

18 

201 

..do.. 

48 

oo 


70-liour ConneUsville. 
ConneUsville. 


Small stove site. 

72-hour; volatile mat ter, 
1.5; ash, 6.5; carbon, 
93.5; sulphur, 0.65. 

Crushed; 4s-hour. 

r v-pmduct: 10 aah. 

88 carbon; 9 as!i; 1 sul¬ 
phur. 

-do.. 


.do. 


12 ash; 1 volatile matter. 

_do. 

72-hour. 

72-h our Connellsv ille; 
natural draft, 3 ounces. 


It. 


It 


} 


R 

sn 


st 

91 


85 

R 

88 

88 


It. II 





30 

50 

20 

3 

9 

2 

75 

12 

13 

2 

10 





6 

5 

5 

4.5 

55 


2i 

Ol 

L x 

4 

40 

60 


5 

5 

5 

Little. 


Mostly 

2 

10 

.... 

60 

40 


2 

10 

.... 

60 

40 


2 

10 


60 

40 


5 

5 

5 


80 

20 

5 

5 

5 


80 

20 

.... 

10 

10 



100 


801 

{ 100 J. 

I 125 I 


<60 


215 
° 200 


300 

50 

80 


300 
60,80 


150 


{'‘“^ 75,400 

<200 


<300 

150 

300 

100 

250 


1,000 

375 

7-50 


1 


3. ROUND, PIT, NATURAL-DRAFT, COKE 


11 

20 

66 

78 

123 

1X5 

137 

195 


Mfg 

Job 


Mfg 

..do. 

Ref 


Ref 


48 

17 

72-hour ConneUsville; 90 
carbon; 13,000 B. t. u.; 
draft,0.2inchof water. 

72-hour ConnellsvUle; 88 
carbon; 11.5 ash; and 
48-hour ConneUsville; 
83 •’ carbon; 14 ash. 

Stove size. 

70 

Mn. 

Bz. 

Y. B. 

20 

6 


30 

70 


60 

250,70 

50 











ConneUsville. 

79 

16 

5 


10 

90 


30-150 


20 

72-hour ConneUsville.. 

73 

21 

3 

3 

None. 


Mostly 

200 

30 

18 

By-product. 

68 

32 




100 

35 

36 

21 

Hall ConneUsville coke; 

SO 

17 

1 

2 



Mostly 

150 



half anthracite coal. 







21 

14 

72-hour. 

66,80 

/Tt, 
\ 16 

V 

1,4 




30 




f 








oAverage. 


5 Patched every 55 heats. 


c Two-thirds coke; one-third coal. 





































































































































































DETAILED RESULTS OF INVESTIGATION 


49 


of furnaces and with various fuels —Continued. 

f indicates that the notes on the reply number affect significance of figures so designated.] 
FURNACES, MELTING LOW-ZINC ALLOYS-Continued. 


Speed of melting. 

Life of crucible. 

Life of lining. 

Fuel consumption per cwt. 

of metai melted. 

Melting 

loss. 

Remarks. 

Heats per day. 

Hours per day. 

Hours per heat. 

Furnaces per ten¬ 
der. 

Metal per furnace 
per day. 

Metal per furnace 
per hour. 

Time per cwt. of 
metal. 

Metal per tender 
per hour. 

Gross. 

Not. 

See notes on pago 

Conditions of test, 

average or special. 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 











Lbs. 









Lbs. 

Lbs. 

Ifrs. 

Lbs. 

Heats. 

Ills. 

coke. 

Pet. 

ret. 



3 

10 

3.3 

6 

333 

33 

3 

200 

3U 

b 300 


4 

1.9 

109 

Average. 

3 

9 

2 


1.50 

17 

6 


35 

7.50 



3 

109 

Do. 

4 

9 

2.2 






22 


35 



109 

Do. 

2 

9 

4.5 

(t) 

240 

27 

3.6 


) 


f e 85 

) 




2 

9 

4.5 

(t) 

360 

40 

2.5 


i a 10 

300 

{ c 57 

\ t3.5 


111 

Do. 

2 

9 

4.5 

(t) 

480 

55 

1.8 


1 


1 c43 




2 

8 

4 

3 

500 

63 

1 6 

190 

25 



2-1.5 


114 

Do. 

4 

9 

2.2 

f2J 

700 

77 

1.3 

192 

32 

400 

40 

1.7 


115 

Do. 

4 

11 

2.7 

8 

800 

73 

1.4 

584 

18 

700 

66 

3 


116 

Do. 

5 

8 

1.6 

5 

690 

86 

1.2 


1-20 

500 

39 

6 

tl.fi 

116 

Do. 


FURNACES MELTING LOW-ZINC ALLOYS. 



o 

— 

10 

5 

4 

300 

29 

3.3 

116 

16 

1,800 

40 

2 . 4 


74 

Average. 


111 


3 







50-60 

f4.5 

3 

77 

Do. 

4 

AX 2 

9 

2.2 

4 

400 

44 

2.2 

176 

35-45 

400 

40 




Do. 

3 

71 

2 5 

4 





13-15 

/ 225- 

\ 63 

13-3 

5-3 

86 

Do. 

2 

1 2 

10 

5 

2 

1,200 

120 

0.8 

240 

20 

V 9UU 
300 

J 

42 

3 

1.5 

102 

Do. 

4 

11 

2.7 

4 

4IX) 

36 

2.9 

204 

36-48 

*600 

25-33 

4 

2 

103 

Do. 

4 

10 

2.5 

2 

1,560 

156 

0.6 

312 

24 

4(X) 

30 

10 

8 

103 

Do. 

2 

9 

4.5 


180 

20 

5 

• 

18-30 

4.50 

55 

tut) 

tD-1(?) 

114 

Do. 


d And German silver. / Patched every 50 heats. h Patched every 21 heats. 

t Special crucible. o In operation 24 hours a day. < I atched every 100 heats. 


44712°—Bull. 73—10-4 




















































































































































50 


BRASS-FURNACE PRACTICE IN TJIR UNITE? STATES 


Detail* of brau-meDing practice in various tyjxt 
(• Designate* estimated results rather than results Ikim* 1 on avernge running conditions; 

4. 8QUARK, PIT, NATURAL-DRAFT, CORK 



46 

Mfg. 

36 

20 

By-product or Connells- 
ville; forced draft, 10- 


(t) 













ounce pressure. 

R. B. 





85 

.do. 

4S 

20 

72-hour. 





100 


HI 

..do.. 

By-product egg; forced 
draft, 20-ounce pres- 

83 

13 


4 

52 













sure. 









60 


ISO 


SO 22.-, 

60 156 


6. SQUARE, PIT, FORCED-DRAFT, COKE 


60 


54 

11 

Two-thirds cuke, one- 

so 

IS 


2 


Mostly. 

None. 

1 35 






tliird coal. 










7. ROUND, PIT, NATURAL-DRAFT, COAL 














































































































































DETAILED RESULTS OF INVESTIGATION 


51 


of furnaces aiul with various fuels —Continued. 

t indicates that the notes on the reply number affect significance of figures so designated.] 
FURNACES MELTING HIGII-ZINC ALLOYS. 


Speed of melting. 

Life of crucible. 

Life of lining. 

Fuelconsumntion per cwt. 

of metal melted. 

Melting 

loss. 

Remarks. 

Heats per day. 

Hours per day. 

Hours per heat. 

Furnaces per ten¬ 
der. 

Metal per furnace 
per day. 

Metal per furnace 
per hour. 

Time per cwt. of 
metal. 

Metal per tender 

per hour. 

Gross. 

Net. 

See notes on page 

Conditions of test, 

average or special. 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

28 

24 











Lbs. 









Lbs. 

Lbs. 

Ifrs. 

Lbs. 

Heats. 

Ms. 

coke. 

Pet. 

ret. 



5 

7 

1.4 

t3 

875 

125 

0.8 

375 

35 

1,100 

24 

4 

2 

80 

Average. 












+3-2 

f 2-1 5 

80 

Do 

1 

6 

6 

8 

350 

58 

1.7 

464 

15 

150 

133 

(°) 

(*) 

92 

Do. 











50 

10-7 


94 

Do. 
















FURNACES MELTING LOW-ZINC ALLOYS. 


t4 

9 

2.2 

5 

000 

67 

1.5 

330 

25 

ft 200 

50 

t5~4 


81 

Average. 

4 

8 

2 

4 

900 

113 

0.9 

4.50 

20-35 

4S0 

44 


2.5 

93 

Do. 

6 

9 

1.5 

3 

930 

104 

1 

310 

38 

IKK) 

53 


1.2 

90 

Do. 


FURNACES MELTING IIIGII-ZINC ALLOYS. 


11 


1.2 


1,200 


109 


0.9 


43(1 


22 


(/) 


60 


84 Average. 


FURNACES MELTING LOW-ZINC ALLOYS. 


4 

10 

2 5 

+8 

1 040 

104 

0.9 

f832 

22 

9 600 

29 

1.5 


78 

3 

9 

3 

8 

' 450 

24-35 

9(H) 

50 

4 

2.3 

79 

o 

11 

1 9 

12 

270 

25 

4 

300 

23 

f9,(HK) 




79* 

4 

9 

2 2 

8 




30-40 

(t) 

(t) 



4 

10 

2 5 

4 

240 

24 

4 

96 

20-40 

300 



5 

11 

2 2 

h 10 

600 

55 

1.9 

550 

30 

*2,250 

46 



84 

4 

10 

2 5 

9 

300 

30 

3.3 

270 

32 

63 

+5. 6 


84 

4 

10 

2 5 

71 

600 

60 

1.7 

450 

28 


38 

+5. 6 


84 

3 

12 

4 

1 2 
5 

775 

65 

1.5 

325 

20-24 

* 450 

42 

3-2.5 

2.5-2 

85 

2 

g 

4 

(l) 

350 

45 

2.3 


20-30 

9(H) 

1(H) 


2 

90 

2 

9 

4.5 

6 

200 

20 

4.5 

120 

25 

150 

75 

t8 

5 

95 

Q 

o 

3 

( n) 

225 

25 

4 



4.50 

44 




A 

o 

9 o 

A 

94 /) 

27 

3 8 

162 

26 

(°) 


P 10-6 


99 

5 

10 

2 

4 

n»GOO 

60 

1.7 

240 

m 16 

30 

10-5 

1.3 

100 

4 

10 

2.5 

4| 

4(H) 

40 

2.5 

160 

48 


40 


*4 



Average. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 


Do. 

Ho. 

Do. 

Do. 


I>o. 

Do. 

Do. 

Do. 


i Patched every 30 heats. 
* Patched every 18 heals. 
/ Over 3. 
m Average. 


n Molder. 

o Patched every 100 heats. 

P Estimated. See notes on reply 107. 








































































































































52 


BRASS-FURNACE PRACTICE IN THE UNITED STATES 


Detail* of braM-melting practice in varioua typeu 

(• Designates estimated results rather than results based on average running conditions; 

7. HOUND, PIT, NATURAL-DRA FT, COAL 




• 














§ 

s 


Analysis or 
charge. 

lompoauion oi 
charge. 

Crucible maker's No. 


Reply No. 

Nature of plant. 

o 

8. 

1 

s 

«-> 

§ 

• 

►pa 

Diameter or inside 
of furnace. 

Fuel and air supply. 

s 

0 

Zn. 

c 

« 

JO 

C* 

New metal. 

Heavy alloy. 

Light alloy. 

5? 

1 

2 

3 

4 

5 

6 

7 

8 

9 

116 

Mfg. 

In. 

In 


Per. 

Pet. 

Pet. 

Pet. 

Pet. 

Pet. 

100 

Pet. 

12 

Lba. 

271 

}. 

121 











/ 40,60. 












\ m 

/ 

128 

130 

Job. 


{1; 

\Epp 

R. B. 






None. 

20-30 

67 


1 ^66. 

83 

0 

4 

5 

25 

50 

25 

4.5-60 

114 

131 

Mfg. 

..do.. 

30 

22 

Egg and stove. 

87 

41 

41 

41 

35 

40 

25 

80 

270 

132 

30 

17 


R. B. 

100 

fiO-80 

213 

138 

130 

..do.. 

18 


It. B. 






90 


..do.. 



85 

5 

5 

5 


70 

. 30 

60 

175 

143 

. .do.. 

30 

16 

Egg. 

R. B 




.50 

Some 

Some. 

30 

.50 

155 

..do.. 

26 

15 


K. B. 




40 

35 

25 

20 

60 

158 


It. B. 




BO 

100 

to 

60 

175 

166 


36 

isl__ 

It. B. 






10 

50 

171 

Job . 

32 

18 

(Stove coal and a little 
\ by-product coke. 

| 80 

6 

0 

5 



125 

375 







172 

Mfg. 

30 

16 _ 

It. B. 







* so 

270 












8 . SQUARE. PIT, N ATUR AL-DR A FT, ( O AL 



21 

Ref. 

36 

2. 


Y. B. 






Mostly 

200 

5Qo| 

11S 

Mfg. 

24 

12 


Y.B. 






30 

(|q| 

122 


1 

80 

15 

5 





H, If 

A 

127 

Mfg. 



Y. B. 






Much, 

40-60 

* 120 

149 

..do.. 

29 

1 

16__ 

66 

27 


7 




40.50 

* 100 

165 

. .do.. 

36 

16 

Egg. 

Y. B. 







45 

wol 

181 

. .do.. 

34 

18 

.do. 

Y. B. 





SO 

20 

60 

170 , 

193 

..do.. 

28 

14 

Draft, 0.8 inch of water.. 

62 

34 

• ••• 

4 


65 

35 

35 



« Patched every 36 heats. 
f> Patched every 20 heats. 
c “Two scuttles.” 


d Molder. 

« Special crucible. 














































































































































DETAILED RESULTS OF INVESTIGATION 


53 


of furnaces and with various fuels —Continued. 

t indicates that the notes on the reply number affect significance of figures so designated.] 
FURNACES MELTING LOW-ZINC ALLOYS—Continued. 


Speed of melt ing. 

Life of crucible. 

Life of lining. 

Fuel consumption per cwt. 

of metal melted. 

Melting 

loss. 

Remarks. 

Heats per day. 

Hours per day. 

Hours per heat. 

Furnaces per ten¬ 
der. 

Metal per furnace 
per day. 

Metal per furnace 
per hour. 

Time per cwt. of 
metal. 

Metal per tender 

per hour. 

Gross. 

Net. 

See notes on page 

Conditions of test, 

average or special. 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

M 

23 

24 











Lbs. 









Lbs. 

Lbs. 

Hrs. 

Lbs. 

Heats. 

Hts. 

coke. 

Pet. 

Pet. 













73 




Average. 

4 on 40 

1 













3 on 60 

l 10 







20-30 

900 




101 

Do. 

2 on 80 

1 













3 

9* 

3.2 

8 

200 

21 

4.9 

168 

f28 

«900 

100 


5-2 

102 

Do. 

3 

9 

3 

8 

342 

28 

2.9 

304 

20-30 

450 

44 

5 

4. 75 


Do. 

3 

10 

3.3 

10 

710 

71 

1. 4 

710 

20 

a 900 

61 




Do. 

3 

11 

3.7 

12 

640 

58 

1.7 

800 

18-23 

900 

62 


*2-1 

102 

Do. 

2 

10 

5 

7 





31 



6 



Do. 

3 

91 

3.2 

7 

525 

55 

1.8 

375 

20 

b 900 

45 


*3 

103 

Do. 

3 

9 

3 


150 

17 

6 


30 

300 

( c ) 

10 

5 

103 

Do. 

4 

9 

2.2 

(<*) 

240 

27 

3.8 


35-40 

700 

40 

4.1 

0.8 

104 

Do. 

3 

H 

3. 7 

6 

525 

48 

2 

288 

18-24 


f50 


3.3 

104 

Do. 

6 

9} 

1.6 

9 

300 

31 

3.2 

280 


j 450- 

60 

3.5 


107 

Do. 



\ 900 

24 





9 

St 

n 

3.8 

6 

750 

100 

1 

600 

20 

600 

coal, 

' H 

• 4 

2.5 

107 

Do. 











coke. 





4 

12 

3 

10 

1,080 

90 

1.1 

900 

20 


30 


2 

107 

d 

w 


FURNACES MELTING LOW-ZINC ALLOYS. 


2 

7 

3.5 

4 

1,110 

160 

0.6 

640 

3 

7 

2.3 

5 

725 

103 

1 

515 

3 

7 

2. 3 


150 

21 

4.9 


3 

6 

2 

(<*) 

170 

28 

3.5 



12 

600 

f35 

0.61 


87 

Special. 

16 

750 

f28 

.62 


87 

Do. 

35 


(/) 

10 

8 -1 

100 

Average 

30 


44 


5-1 

114 

Do. 


FURNACES MELTING IIIGH-ZINC ALLOYS. 


9 

V 

4.5 

4 

4 

(?) 

2 

5 

1,000 

180 

250 

360 

111 

23 

28 

40 

0.9 

4.2 

3.6 

2.5 

444 

25-35 

200 

*25 

*80 



78 

101 

Average. 

Do. 

9 

9 

3 

3 

56 

200 

10-15 

49-50 

900 

450 

70 

4-2 

4 

3-2 

102 

Do. 

Do. 

10 

3.3 

7 

300 

30 

3.3 

210 

45 

/ 

\ 900 

} 100 


*3 

104 

Do. 

10 

1.7 

7 

600 

60 

1.7 

420 

29 

900 

33 

15-10 

5-3 

107 

Do. 

8 

2 

9 

680 

85 

1.2 

735 

17 

»2,400 

fioo 

3 


109 

Do. 

10 

2 

8 

425 

43 

2.3 

344 

27* 

440 

35 

12 

4 

113 

Do. 


/ Over 66, 

g Over 3. 


h Average. 

i Patched every 25 heats. 












































































































































f>4 


BRASS FURNACE PRACTICE IN TIIK 


UNITED STATES. * 


Details of brass-melting practice in various tyi** 
|* Designates estimated reculu rather than results based on avenge running conditions; 

10. BQUAItK-PlT, NATURAL-DRAFT, COAL 


Reply No. 

Nature of plant. 

o 

8. 

3 

* 

§ 

4> 

S 

S 

Diameter or inside length 
of furnace. 

Fuel and air supply. 

Analysis of 
charge. 

Composition of 
cWrge. 

Crucible maker's No. 

o 
*» 
i 3 

s 

« 

is 

9 

3 

U 

Zn. 

C 

<Xl 

£ 

1 

l 

A 

Heavy alloy. 

• 

C 

~a 

u. 

,J 

1 

2 

4 

& 

6 

7 

8 



In. 

In. 


Pet. 

Pet. 

Pet. 

Pel. 

Pet. 

Pet. 

Pet. 


Lbs. 

17 

Roll 


16 


65 

35 



35. 

65 

60 

100 

t»5 

.do.. 

33 

15 

Egg Cool; 14.IKM) It.t.ll. . 

66 

34 



30 


70 

70 

200 

140 

. .do.. 

39 

16A 

Eirt . 

66 

34 .... 


60 

13 

27 

80.90 

220 

141 

. .do.. 


45 

90 jior cent of crud, 1ft per 

70 

30 



6) 

40 


70 

100 





cent of coke; Jraft', 1 




% 










inch of water. 










151 

. .do.. 

30 

15 

Egg. 

66 

31 



66 

34 


70 

200 

189 

. .do.. 


1'. 

Einr 13.000 B. t. u 

65 

35 



75 

25 



2401 

189 

. .do.. 


IK 

.do. 

65 

35 



40 

00 



450 

192 

. .do.. 



("oa 1 and litt lo coke 

65 

3.5 






SO 


194 

. .do.. 

4H 

16 

Eek. 

65 

35 





65. 70: 

1st) 

200 

..do.. 

33 

16 

Coal and little coke. 

6 65 

35 






60 

ISO 


11. ROUND, TIT, FORCKD-DItAFT, COAL 


4 

Mfg. 

..do.. 

23 

13 

Rangecoal; forced draft, 
11-ounce pressure. 

.do. 

R. B. 







30 

.00 

4 

25 

15 

R. B. 







so 

100 

4 

. .do.. 

34J 

34 

22 

.. do. 

R. B. 








12 

. .do.. 

161 

tl6 

12 

i Forced draft, 24-ounce 

}Rll. 





100 


J40,60. 

\ f 125 

22 

. .do.. 

30 

\ pressure. 

1-ounce pressure. 

R. B. 






1 BUJ 

100 240 

56 

. .do.. 

24 

Nut amf nmge coal; 30- 
pouml (?) pressure. 
Range coal; “fan pres¬ 
sure.” 

R. B. 







40 

100. 

57 

Job . 

30 

IK 

It. B. 







45,50 

20 

c ]Q0 

115 

Mfg. 

..do.. 

/ 

24 

\t\ 

It. B. 







Ji 

1K5 

34 

16 

9-ounce pressure. 

It. B. 







K0 

225 











12. ROUND, 1»IT, FORCED-DRAFT, COAL 


24 

Mfg. 

42 

22 

62 

..do.. 

30 

17 

99 

..do.. 


14 

147 

..do.. 

24 

16 


Coal, 12.170 B. t. u., 13 
per cent of ash; and 
coke, 11.4 per cent of 
ash ,f 3-ounce pressure. 

1 t.'-oo li. t. II. 

10K>unce pressure. 

Stove size. 


Mn. 




no 

40 


200 

- ;j 

Bz. 









72 

26 


2 

20 

so 


60,70 


79 

131 

31 

3 




60 

142 

Y. B. 




K0 

20 

50 

1 


6 And some German silver. 


c Average. 


a Patched every 100 heats. 



























































































































































DETAILED RESULTS OF INVESTIGATION 


55 


of furnaces and with various fuels —Continued. 

t indicates that the notes on the reply number affect significance of figures so designated.] 
FURNACES MELTING HIGH-ZINC ALLOYS. 


Speed of melting. 

Life of crucible. 

Life of lining. 

Fuel consumption percwt. 

of metal melted. 

Melting 

loss. 

Remarks. 

rj 

t* 

& 

CO 

V 

<3 

O 

HH 

Mi 

Hours per day. 

Hours per heat. 

Furnaces per ten¬ 
der. 

Metal per furnace 
per day. 

Metal per furnace 
per hour. 

Time per cwt. of 
metal. 

Metal per tender 

per hour. 

Gross. 

Net. 

See notes on page 

Conditions of test, 

average or special. 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

oo 

23 

24 












Lbs. 









Lbs. 

Lbs. 

Ilrs. 

Lbs. 

Heats. 

Ills. 


coke. 

Pet. 

Pet. 



4 

9 

0 0 

31 

640 

70 

1. 4 

231 




39 

3.5 


76 

A verage. 

5 

10 

2 ' 

34 

1,000 

100 

l 

333 

30 

a 500 


33 

3 

2 

97 

Do. 

5 

94 

1.9 

34 

1.100 

114 

0.9 

380 

19-32 

, .id 


33 

4 

2 

103 

Do. 

8 

10 

1.3 

13 

1,520 

152 

0.6 

252 

25 

1,000 


33-37 

3.65 

2.22 

103 

Do. 

5 

10 

2 

34 

1,000 

100 

1 

333 

30 



30 

3 

2.5 

104 

Do. 

5 

9 

1.8 

34 

1,200 

133 

0.7 

430 

40 

960 


35 

1.75 

1.25 

112 

Do. 

5 

9 

1.8 

24 

2,250 

250 

0.4 

625 

40 

960 


33 

1.75 

1.25 

112 

Do. 









35 



30 

3 

1.5 

113 

I)o. 

5 

94 

1.9 

2§ 

900 

95 

1 

255 

55 



28 


2 

113 

Do. 







50.3 





4 

10 

2.5 

34 

64!) 

64 

1.5 

213 

30 

600 


Coal, 

11.2 

6.5 


114 

Do. 












Coke 






FURNACES MELTING LOW-ZINC ALLOYS. 


4 

9 

2.2 

6 

4(H) 

44 

2.1 

264 









5 

84 

1.7 

10 

625 

75 

1.3 

750 

4 

10 

2.5 

34 

1,160 

116 

0.9 

416 

3 

9 

3 

6 

300 

33 

3 

198 

3 

9 

3 

5 

300 

33 

3 

165 

2 

74 

3. 7 


120 

16 

6.3 


3 

10 

3.3 

5 

675 

68 

1.5 

340 


40 

400 

29 


0.5 

72 

Average 

35 

400 

26 


0.5 

72 

Do. 

23 

400 

f_>7.5 


0.5 

72 

Do. 

1.8-23 

480 

119 

*3 


74 

Do. 

22 

d6<)0 

30 

4-5 

3 

78 

Do. 

35 

900 

30 

6.7 

*5 

83 

Do. 

30 

900 

30 

*5 



Do. 

45 

300 

125 



1(H) 

Do. 

10-18 

4.50 

52 



109 

Do. 


FURNACES MELTING IIIGH-ZINC ALLOYS. 


1 

5 

5 

4 

600 

120 

0.8 

480 

115 


(0 

5 


78 

Average. 

4-5 

10 

2-2.2 

7 

c 845 

85 

c 1.2 

c595 

25 

330 

28.5 

3 

1 

84 

Do. 

3 

10 

3.3 

9 

425 

43 

23 

390 

23 

600 

41 

*3.5 

*3 

97 

Do. 

4 

10 

2.5 

t 

580 

57 

1.9 

400 

32 

600 

50 

5 

3. t 


Do. 


d Patched every 4 heats. < 40 pounds of coal and 10 pounds of cuko. 



























































































































50 


BRASS FURNACE PRACTICE IN T1IK UNITED STATES 


Details of brass-melt iny practice in various tyjx* 
|* ltaHl£nuUv> estimated results ruther than results hued on average running conditions; 

13. HOUND, TILTING, FORCED-DRAFT, COKE 



41 

90 


154 

ISO 


Mf,; 

.do..! 30 


.do. 

.do. 


19 


Hv-produot; 2-oun<?e 
forced draft. 

72-hour Connellsville; 
forced draft, 1.5 to 2 
ounces. 

Forced draft, 2 pounds.. 
72-hour Connellsville_ 


G5 

60 


GO 

Mn. 

Hz. 


34 

34 

32J 


.... 

1 



.... 

1» 

None. 





SO 


100 


20 

25 

Some. 

225 

Tall 




15. SQUARE, TILTING, FORCED-DRAFT, CORK 


79 

Mfe 

36 

24 

Connellsville: forced 

OS 

32 



33 


67 


J 


Roll. 



draft, 3 ounces. 











o Patched every 15 heats. b Patched every 18 heots. 
























































































































DETAILED RESULTS OF INVESTIGATION 


57 


of furnaces and with various fuels —Continued. 

f indicates that the notes on the reply number affect significance of figures so designated.]' 
FURNACES MELTING LOW-ZINC ALLOYS. 


Speed of melting. 



£ 

o 

t— 

Melting 

loss. 

Remarks. 

Heats per day. 

Hours per day. 

Hours per heat. 

Furnaces per ten¬ 
der. 

Metal per furnace 
per day. 

Metal per furnace 
per hour. 

Time per cwt. of 
metal. 

Metal per tender 

per hour. 

Life of crucible. 

Life of lining. 

Fuel consumption p 

of metal melte* 

CO 

CO 

O 

l* 

o 

•J 

at 

fc 

See notes on page 

- 

Conditions of test, 

average or special. 

10 

11 

12 

13 

14 

15 

10 

17 

18 

19 

20 

21 

22 

23 

24 

10 

10 

1 

1 

Lbs. 

6,000 

Lbs. 

600 

Ilrs. 
0.17 

Lbs. 

600 

Heats. 

f40 

Ilts. 

1,200 

Oats. 

oil. 

17.5 

Pet. 

5.5 

Pet. 

2 

72 

Average. 

6 

9 

1.5 


3,000 

330 

.35 


50-60 


J 13- 
\ 16.5 

} 4 

2.2 

79 

Do. 



/ 900- 
\ 1,200 

1 




6 

10 

1.7 

2 

3,600 

360 

.28 

720 

16 

| 17.3 

2.2 

o 

84 

Do. 

5 

n 

4 

1.5 

2 

1 

3,000 

400 

350 

.25 

.29 

40(1 

21 


21 

ii. »; t 


87 

Special. 

Average. 

2 

4 

1,400 

28 

1,200 

36 

4-1.7 

3-1.4 

• 

98 

3 

12 

9 

11 

7 

4 

2 

1,350 
2,250 

2,580 

135 

250 

235 

.75 
. 40 

270 

1,000 

20-25 

12 

(«) 

27 

1 



Do. 

t3 

6 

6 

3 

4 

40 

f0.51 

5 

1.1 

f 1. NO 

2 

104 

Do. 

1.8 

1.2 

2 

.43 

470 

tss 

40 

t-150 

22 

20 

107 

116 

Do. 

Special. 











FURNACES MELTING IIIGH-ZINC ALLOYS. 


4 

6 

10 

10 

2.5 

1.7 

3 

1 

2,400 

2,640 

240 

264 

041 

.36 

720 

264 

f45 

61,000 

25 

15 


4 

4.9 

81 

95 

Average. 

Do. 

4 

10 

2.5 

1 

2,000 

200 

. 50 

200 

20 

300 

f7.5 

5 

3 

104 

Do. 

4 

9 

2.2 

2 

1,800 

200 

.50 

400 

t40 

600 

20 

3 


109 

Do. 


FURNACES MELTING HIGII-ZINC ALLOYS. 


6 

8 

1.3 

2 

4,000 

500 

0.20 

1,000 

3-48 

(0 

15 

2.8 

0.9 

87 

Average. 


c Patched every 12 to 15 heats, 


























































































































f)S 


BRASS-FURNACE PRACTICE IN THE UNITED STATES 


Detail* of hraxx-mcltintj practice in varuma typfi 
(• Designates estimate*! rmulU rut her than result* Imu**] on average running conditions; 

16. HOUND, PIT, OIL FURNACES, WITH LOW 


6 

Z 

C. 

K 

Nature of plant. 

Height or shape of furnace. 

Diameter or inside length 
of fcimace. 

Fuel and air supply. 

Analysis of 
charge. 

Composition of 
cluirge. 

6 

A 

m 

V- 

£ 

a 

8 

u 

f 

1 

W 

O 

• 

if 

O 

K 

V 

h 

s 

i 

•U 

H. t. u. per pound 
or per cubic foot. 

Air pressure at 
burner. 

Pressure of luel at 
burner. 

• 

3 

6 

c 

N 

Sn. 

22 

New metal. 

e 

*3 

>> 

> 

2 

Light alloy. 

1 

2 

3 

4 

to 

to 

5c 

to 

6 

7 

8 

0 



In 

7n 


Per lb. 

Ox. 

Lbs. 

Pet. 

Pet. 

Pet. 

Pet. 

Pet. 

Pet. 

Pet. 


Lb*. 

3 

Mfg. 

35 

20 

0. 88| 

19,000 

6 

40 

83$ 

8 

4$ 

4 

50 

40 

10 

70,80 

a 220 

14 

Ref 

27 

23 

.85 


G 

25 

85 

5 

4 

6 



Mostly 

6 250 

0a)0 

40 


30 

Mft- 

l 


18 

15 

85 

5 

5 

5 



40-200 


4.1 

Job 

\2S 

1 

. 8S 


16 

35 

82 


4 

11 




SO 

244 

52 

Mfg. 



. S'.l 

(t) 



84 

10 

3 

3 

15 

75 

io 

45,70 

o 146, 

54 

.do.. 




18 


R. R. 







00 

ian 

75 

do . 

20 

16 



10 

25 

84 

(O 

4 

(*) 




50 

150. 

102 

Job . 




2-5 

:r 

85 

5 

5 

5 

Some. 

Some 

Some. 

80,12.1 


103 

.do.. 


(t) 

. sy 

19,500 



R.R. 




70 

30 


80 

220 

134 


~32 

IS 

ft) 

(t) 

(t) 

(t) 

(t) 

(t) 

(t) 

(t) 

12 

88 


GO 

Iso 

157 


2s 

1> 

.81 

10 

10 

85 

5 

5 

5 




70 

2m; 

W, 







84 

4 

5$ 

5$ 




70 

2110 

1 ss 

M fg. 

34 

21 

. SO 

19 00Q 

K 

tio 

R. B. 



55 

45 

17.1 

a 33 ft 

188 

..do.. 

30 

22 

• SO 

19,0IN> 

_ 

00 

R. B. 





55 

45 

125 



17. SQUARE, PIT. OIL FURNACES, WITH LOW 


106 

Mfg. 
..do.. 

an 1 


I/)W. 

30 

Bz. 







.10 

150 

150 

22j 

16 0.86 . ... 

V32 

17 

Bz. 





100 


100 

275 










IS. ROUND, PIT, OIL FURNACES, WITH LOW 


1 

Mfg. 

20 

16 

0.87 


16 

15 

GO 

35 


5 

20 

GO 

20 

GO 

180 

20 

Job . 



. 86 


16 

30 

iMn. 




50 

50 




93 

Mfg. 

16 

15 



16 

30 

\Bz. 

74 

1 

14 

3 

5 




50, 60 

a 140 

93 

do.. 

16 

1.1 



16 

30 

74 

14 

3 

5 




80 

170 

94 

.do.. 





20 

20 

83 

13 


4 

52 



GO 

175 

146 

Job 



.85 


20 

15 

67 

29 


4 

None. 

Mostly. 

Some. 

70 

iso 

181 

Mfg. 





6 

40 

Y. B. 





80 

20 

GO 

170 

189 

Ref. 







65 

35 





100 


250, 400 


















19. ROUND, PIT OIL FURNACES, WITH HIGH 








Lbs. 











8 

Job . 



0.88 

19,250 


35 

85 

5 

5 

5 

75 

25 


80 

2qqI 

44 







85 

7$ 

7$ 





70,100 

a 200 

50 

M fg 

30 

16 

.91 


4 


82 

6 

6* 

6 




SO 

208 

86 

. .do.. 

27 

16 

.95 

118,800 


20 

R. B. 







100 








Bz. 








88 

.do 

24 

18$ 



5 

41 

R. B. 







60 

175i 

136 





t4 80 

It. B. 






Some. 

60 

17o! 

















o Average. 
t> Special crucible. 


« 21 heats with No. 45 crucible and is heats with No. 70 crucible 
d Patched daily. 

















































































































































































DETAILED RESULTS OF INVESTIGATION 


59 


of furnaces and with various fuels —Continued. 

t l ndicates that the notes on the reply number affect significance of figures so designated.] 
PRES9URE AIR, MELTING LOW-ZINC ALLOYS. 


Speed of melting. 

Life of crucible. 

Life of lining. 

Fuel consumpt ion perewt. 

of metal melted. 

Melting 

loss. 

Remarks. 

Heats per day. 

Hours per day. 

Hours per heat. 

Furnaces per ten¬ 
der. 

Metal per furnace 
per day. 

Metal per furnace 
per hour. 

Time per ewii. of 
metal. 

Metal per tender 

per hour. 

Gross. 

Net. 

• 

See notes on page 

Conditions of test, 

average or special. 

10 

11 

12 

18 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 











Gals. 









Lbs. 

Lbs. 

Hrs. 

Lbs. 

Heats. 

llts. 

oil. 

Pet. 

Pet. 



9 

9 

1 

4 

2,000 

222 

0. 45 

888 

40 

1,350 

+2.2 

1.5 

1.0 

70 

Average. 

t3 

11 

3.6 

3 

fl, 950 

fl80 

0.6 

f540 

17 

480 

2.8 

3.7 


74 

Special 

6 

8 

1.3 

2-5 





10-30 

9(H) 

3 


5 

81 

A ye rage. 

9 

10* 

1.2 

6 

2,200 

210 

0.5 

1,320 

36 

c 700 

(t) 

6 


81 

Do. 

4 

7 

1.7 

4 

575 

82 

1.2 

328 

( f ) 

<12, 4(H) 

3 

4.7 

3.7 

82 

Do. 

7.6 

1U 

1.6 


1.4(H) 

120 

II. s 


35 

2,200 



*2 5 

S3 

Do. 

6 

9* 

1 5 


9(H) 

1(H) 

1 


25-30 

9(H) 

3 

*5-4 

*3 

86 

Do 

7 

9 

1.3 

4 





20-35 

450 

3. 5 

7-3 

5-2 

98 

Do. 

4.5 

8 

1.9 

4 

980 

120 

0.8 

480 

18 

<•4.800 

2.3 


9s 

Do. 

(t) 

(t) 

1 



ISO 

0.55 


20 

(t) 

6 


102 

Do. 

6 

10 

1. 7 

5 

1,200 

120 

0.8 

600 

43 

1,800 

(t) 



105 

Do. 

6 

9 

l. 5 


1,200 

133 

0. 75 


90 

2. 3 



109 

Do. 

2.4 

4.2 

1.7 

(t) 

200 

0. 5 


a 15 

375 

3.5 

t3.5 


111 

Do. 

2.4 

4.2 


(t) 








111 

Do. 

















PRESSURE AIR, MELTING LOW-ZINC ALLOYS. 


3 

10 

3.3 

3 

4.50 

45 

2.2 

135 

23 




(/) 

98 

Average. 

3 

9 

3 

5 

850 

95 

I 

475 

20 


7.8 

3 

1.5 

104 

Do. 


PRESSURE AIR, MELTING IIIOII-ZINC ALLOYS. 


8 

10 

1.2 

4 

1,440 

144 

0.7 

576 

28 


1.8 

2 

4.7 

6 

6 

1.7 

5 

0.75? 

70 

77 

96 

96 

96 

104 

109 

112 

Average. 

Special. 

Average. 

Do. 

Do. 

Do. 

Do. 

Do. 

— 

7 

6 

9 

5 

10 

10 

9 

10 

1.4 

1.7 

1 

2 

5 

5 

3 

3-1 

980 

1.020 

1,575 

900 

98 

102 

158 

90 

1 

1 

0.5 

1 . 1 

490 

510 

574 

305 

26-30 

51,49 

33 

33 

50 

25-28 

1,050 

(o) 

3.5 

3.5 

3 

(t) 

3.2 

5 

5 

1.5 

4 

10 

2.5 

5 

(1,000, 
\l, 600 

1(H), 

160 

y 1—0- 6 


400 



PRESSURE AIR, MELTING LOW-ZINC ALLOYS. 


ej 

4 

10 

1.4 

8 

1,400 

140 

0.7 

1,120 

23 

780 

2.2 

1.6 


73 

Special. 

3 

9 

3 

3 

6(H) 

67 

1.3 

2(H) 

6-12 

(A) 

3.3 

6 


81 

Average. 

4 

9J 

2.4 

5 

836 

90 

1.1 

450 

19 

6(H) 

2.3 


4 

82 

Do. 

3 

g 

2 7 

2 

810 

1(H) 

1 

2(H) 

20 


*2 


U) 

93 

Do. 

7$ 

9$ 

1.3 

4 

1,320 

140 

.7 

560 

35-82 

1,900 

2.2 

5.5 

95 

Do. 

6 

10 

1.7 

5 

1,000 

100 

1 

500 

42 


3 



103 

Do. 


e Some. . o Patched every 60 heats. * Gravity. 

/ Less than 1 per cent. A Patched every 18 heats. J Estimated to be less than 2 per cent. 































































































































































GO 


BRABS-FU KNACK PRACTICE IN TIIE UNITED STATES 


Detail* of brn*t •melting practice in variou* tyjx* 

i* Designates estimated results rather than results based on average running conditions 

20. HOUND, PIT OIL FURNACES, WITH HIGH 


Reply No. 

Nature of plant. 

Height or shape of furnace. : 

- 

1 

* 

I? 

ii 

. V"* 

a z 

0 

s 

£ 

Fuel and uir supply. 

Analysis of 
charge. 

Composition of 
clwrge. 

Crucible maker's No. 

• 

O 

6* 

M 

# 

c 

►e 

— 

s 

l 

oo 

R. t. u. per pound 
or per cubic foot. 

Air pressure at 
burner. 

Pressure of fuel at 

burner. 

• 

5 

e 

N 

d 

ca 

25 

£- 

New metal. 

•Aorw Aaboh 

Light alloy. 

1 

2 

3 

4 

oa 

56 

5r 

5 d 

6 


f* 

7 


8 

9 



In. 

7n 


Prr lb. 

Or. 

Lbs. 

ret. 

ret. 

L 

ret. 

Pet. 

ret. 

Pet. 


Lb$. 

25 


IS 

15 

0. Mi 

18,000 

16 

29 

M n. 




2.5 

50 

25 

20-60 

o 125 







ID.. 









100 

M hr 

24 

17 

vs 


15 

1 

Y. R. 







4.5 

l.ioi 

124 

do 


.9.5 


20 

10 

V. B. 



33 

67 


45,50 

a I .‘15 

160 

..do.. 

24 

“ai 

.88 


10 

20 

75 

15 

5 

5 

30 

L * 

25 

125 



21. PIT, OIL FURNACES, WITH HIC.II-PKK88URE AIK AND 


58 


(*) («) 




6 

(/) 

R. B. 








ion 


3.-5 (*) 


22. PIT, OIL FURNACES, WITH HIGH-PRESSURE AIR AND 


(0 


(0 


0.89 



7* 


73J 


22! 1J 


20 


35 (*) 


23. PIT, NATURAL-DRAFT, OIL FURNACES, WITH 


198 


(t) 


(t) 


0. S3 


(t) 


(t) 


It. II. 


33 


4? 25 


40, 


& 


24. ROUND. PIT, NATURAL-GAS FUR 


15 

Mfg. 

..do.. 




Per 

CH.ft. 

1,659 

Oz. 

20 

Oz. 

41 

841 

85 

120 

178 

20 

34 






201 

Job. 

4!^ 

22 


1,000 

4 

7 

80 





5 


«1 

5 


10 


2 } 

5 


10 


20 

35 

50 

45 







00 

25 

40,50. 


60 


20.25 

100 

200 


ISO 
0 155 


3 


25. ROUND, ITT, CITY-GAS FURNACES 


12 

94 

108 


Mfg. 

..do.. 

3.5 

17 











590 

680 

625 


24 

20 

t4H 


4 

2 

6 


85 

S3 

88 


5 

13 

5 

5 

4 



None. 

Some. 

37 

Some. 








00,80 

70 

50 


a 200 
185 
150 


26. ROUND, ITT, PRODUCER-GAS FUR 


164 Mfg 


130 




R.B 


50, Some. 


Some. 

70 

200 


• 



a Average. 

t> Patched every 70 heats. 
r Patched every 90 heats. 
<* Patched dally. 


« Pit dimensions, 10 by 21 inches. 

/ Gravity. 

0 108 pounds per crucible. 

A Results based on use of two crucibles per furnace. 
























































































































































































































DETAILED RESULTS OF INVESTIGATION 


Cl 


of furnaces and with various fuels —Continued. 

t indicates that notes on the reply number affect significance of figures so designated.] 
PRESSURE AIR, MELTING HIGH-ZINC ALLOYS. 


Speed of melting. 

Life of crucible. 

Life of lining. 

Fuel consumption per cwt. 

of metal melted. 

Melting 

loss. 

Remarks. 

Heats per day. 

Hours per day. 

Hours per heat. 

Furnaces per ten¬ 
der. 

Metal per furnace 
per day. 

Metal per furnace 
per hour. 

Time per cwt. of 
metal. 

Metal per tender 

per hour. 

Gross. 

Net. 

See notes on page 

Conditions of test, 

average or special. 

10 

11 

12 

13 

14 

15 

IB 

17 

18 

19 

20 

21 

22 

23 

24 











Gats. 









Lbs. 

Lbs. 

Mrs. 

Ijbs. 

Heats. 

Hts. 

oil. 

Pet. 

Pet. 



6 

8 

1.3 

4 

750 

9-4 

1.1 

375 

* 30 

2,400 


10 


79 

A vornro 

6 

9 

1.5 

4 

780 

85 

1.2 

340 

45-50 

hi,800 

*5 

4 

3.5 

97 

Do. 









t12-30 

(<■) 


*10 


10* *2 

T) n 

3 

10 

3.3 

3 

1,050 

105 

0.95 

315 

17-20 

d 450 

2 

6-4 

3-2 

105 

Do. 

SEVERAL 

CRUCIBLES, MELTING LOM 

-ZINC ALLOA'S. 






3 

8 

2.7 


64H 

81 

1.2 


15 

150 

*2.8 

1.5 


83 

(*) 

SEVERAL 

C RUCIB LES, M E LTING 

HIGH-ZINC ALLOYS. 






3 

10 

3.3 

1 

1,6,SO 

168 

0.6 

168 

18] 

90 

5.6 


3.8 

72 

(*) 


SEVERAL CRUCIBLES, MELTING LOW-^INC ALLOYS. 


4 

11 

2.7 

2 

3,000 

273-382 

0.33- 

546- 

»15 

ml ,500 

*1 

2.1 

2.05 

114 





4, (KM) 


0.27 

764 








NACES MELTING LOW-ZINC ALLOYS. 

« 


7 

2 i 

3 

3J 

9 

8 

6 

8 

1.3 
3.5 

2 

2.3 

4 

3 

1,280 

360 

142 

45 

24 

260 

0.7 

2.2 

4 

.4 

568 

135 

1,040 

55 

oil 

22-32 

15 


Cu.ft. 

gas. 

310 


1.4 

74 

101 

108 

114 

Average. 

Do. 

Do. 

Special. 

175 

4.3 



4 

2,275 

800 

231 

2.25 




MELTING 

LOW-ZINC ALLOYS. 










5 

7 

1.4 


1,000 

142 

0.7 


25 


650 


2.3 

74 

A verage. 

9 

9 

1 

3 

1,665 

185 

.5 

555 



382 

5.7 

2.2 

% 

l>o. 

8 

10 

1.2 

8 

1,200 

120 

.8 

960 

45-60 

900 

256 


1.25- 

99 

(») 













1.50 




NACES MELTING LOW-ZINC ALLOYS. 


10 1.4 


1,400 


140 


0 .' 


1,120 


]20 


p525 3,500 


fl-0. 75 


100 


Special. 


i Pit dimensions 40 by 27 inches by 30 inches high. 

* 60 pounds per crucible. 

l Results based on use of seven crucibles per furnace. 
•n Patched every 300 heats. 


« Results based on siv crucibles per furnace. 
o Three burners per furnace. 
p Patched every 40 heats. 





















































































































































































02 


BRASS-FURNACE PRACTICE IN THE UNITED STATES 


Details of brass-meltiruj practice in various tyj*es 

|* Dfwignatcs estimated results ratlier titan result* based on average running condition*; 

27. ROUND, TILTINO, NATURAL-OA8 


o 

A 

>, 

c. 

- 

sc 


7 

15 

55 

112 

145 

167 


Nature of plant. 

Height or shape of furnace. 

Diameter or inside length 
of furnace. 

P uel and air stipply. 

Analysis of 
charge. 

Composition of 
charge. 

Crucible maker’s No. 

Weight of charge. 

c 

K 

V 

N 

o ° 

c 

l 

co 

B. t. U. per pound 
or per cubic foot. 

A ir pressure at 
burner. 

Pressure of fuel at 
burner. 

Cu. 

Zn. 

c 

CO 

• 

fk 

e-a 

New metal. 

Heavy alloy. 

Light alloy. 

2 

3 

4 

5a 

56 

5c 

id 

6 

7 

8 

9 





Per 













In. 

In. 


cu.ft. 

Or. 

Lbs. 

Pet. 

Pci. 

Pet. 

Pet. 

ret. 

Pet. 

Pet. 


Lbs. 

Job 







It. lit 







125 

300| 

Mfg 




1.05H 

20 

44 

87 

Si 

Si 

14 


100 


125 

305 

(lo 




mo 


8 

R. B. 




125,275 


do 







It. B. 







450j 

<)n 

22 

i^4 



16 

6 

85 

44 

6i 

4 

15 

.50 

35 

125 


..do.. 

2s 

174 





R. B. 






70 

lxd 


* • 2 















2S. ROUND, TILTINO, OIL FURNACES, WITH LOW- 



98 

tS9 

189 

Mfg. 

Ref. 

_ .do.. 



tO. 93 

19,500 

16 

25 

80 
Y. B. 

16 

24 

i 

40 

60 

100 


125 

J 






























30. ROUND, TILTINO, OIL FURNACES, WITH 


Mfg 



0.87 

19,000 

8 

15 

87 

4 

34 

24 

25 

50 

25 

150 

4tJ 

do.. 

28 

28 

.80 

3 

20 

Bz. 


1(K) 



125 

• 71*1 

. .do.. 





34 

6 

(t) 





Mostlv. 


125 

375 






3 


It. It. 





100 


125 

34 

M fg 


24 



25-30 

3 

It. B. 







125 

•u*y 

. .do.. 

34 

24 

(') 


+ 140 

15 

80 

4 

8 

4 

60 

40 


300 


do.. 



.91 


80 

60 

R. It 




10<V 



125 


..do.. 

29 

184 

. 8* 

19,000- 

12-20 

34 

90 

1 

8 

i 

45 

35 

20 

275 

750* 





19.300 












Job 



</) 

(/) 

7-10 


It. B. 





Some. 

Some. 

125 

200 




tio 

SO 

85 

5 

5 

5 




125. 















150,275 



« Average. <* Patched every 23 heats. 

p»«rial rrueiblc. « Less than 0.94. 

e patched every 15 heats. 
































































































































































































DETAILED RESULTS OF INVESTIGATION 


G3 


of furnaces and with various fuels —Continued 

t indicates that notes on the reply number affect significance of figures so designated.] 
FURNACES MELTING LOW-ZINC ALLOYS. 


Speed of melting. 

Life of crucible. 

| Life of lining. 

Fuel consumption per cwt. 

of metal melted. 

Melting 

loss. 

Remarks. 

Heats per day. 

Hours per day. 

Hours per heat. 

Furnaces per ten¬ 
der. 

Metal per furnace 
per day. 

Metal per furnace 
per hour. 

Time per cwt. of 
metal. 

Metal per tender 

per hour. 

Gross. 

Net. 

See notes on page 

Conditions of test, 

average or special. 

,0 

11 

12 

18 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 











Cu.ft. 









Lbs. 

Lbs. 

llrs. 

Lbs. 

Heats. 

Jits. 

gas. 

ret. 

I'ct. 



6 

9 

1.5 

4 

1,800 

200 

0.5 

800 

20 



6 4 


73 

Average. 

8 

9 

1.1 


2,240 

220 

.45 


38 




1.5 

74 

Special. 


9 









5 


83 

A verage. 

2 

12 

6 (?) 

2 

900 

75 

1.3 








Do. 

2-5 

10 

5-2 


a 687 

69 

1.5 

215 

18 


480 

7.3 

5.8 

103 

Do. 

6 

9 

1.5 

4 

1,080 

120 

.8 

480 

1 * 

450 

440 

5 

3 

107 

Do. 


PRESSURE AIR, MELTING LOW-ZINC ALLOYS. 


JL 












Gals. 















oil. 





4 

10 

• 2.5 

6 

1,000 

100 

1 

600 

29 

(t) 

3 

4 

3-2.5 

74 

Average. 

7 

11 

1.7 

5 

1,680 

153 

0.7 

765 

21 } 

525 

(t) 

1.5 


74 

Do. 

|3 

10 

3.3 

2 

1,500 

150 

.7 

300 

20 

350 

2.5 

3.5 

2.75 

79 

Do. 

5 

10 

2 


2,500 

250 

.4 


19 

550 

2 . 6 



80 

Do. 

6 

lli 

1.9 


L 500 

130 

.8 


33 

1,500 

* 2 .5 


3.5-3.0 

• 83 

Do. 

5 

x 1 2 
10 

2 

2 

5, (XX) 

500 

.2 

1,000 

12 

900 

2.5 

2.5 


84 

Do. 

2 


3 5 

2 

1 200 

170 

.6 

340 

3-10 


3.3 

*9 8 


86 

Do. 

R 

8 

1 () 

2 

3^ 250 

405 

.25 

810 

22 


1.9 

0.42 


87 

Special. 

4 

9 

2 2 

4 









98 

Average. 

a 

10 

3 3 

2 


98 

1 

198 

10 is 


(t) 



101 

Do. 

A 

8 

9 

3 

1 080 

135 

. 8 

405 

18 


3 

6.5 


103 

Do. 

4 

10 

2.5 


3,350 

335 

.3 



1,200 

1.2 

1.5 

1 

108 

Do. 

7? 

2 





h 



1.6 


110 

Do. 

1 2 
















PRESSURE AIR, MELTING IIIGII-ZINC ALLOYS. 


6 

3 

2 

8 

10 

10 

1.3 

3.3 
5 

3 

3 

2 

1,800 

1,300 

1,600 

225 

120 

160 

0.45 
.8 
.55 

675 

360 

320 

25 

27 

32 

6.50 

300 

2(X) 

3-2.5 

3 

5.5 

* 0 .5(?) 

97 

112 

112 

Average. 

Do. 

Do. 






IIIGH-PRESSURE AIR, MELTINC 

I LOW-ZINC ALLOYS. 



• 



5 

9 

1.8 

2 

2, (XX) 

222 

0.45 

444 

27 

1,000 

3 

|5.4 

4.4 

77 

Average. 

9 

fi 

4 


4(X) 

50 

2 


16 

(c) 


4.1 


79 

Do. 

5 

94 

1.9 

2 

1,875 

195 

.5 

390 

25 

00 

t5 

*5 


80 

Do. 

o 

Q 

A 

2 

600 

75 

1 3 

150 

32-35 


3.7 

3 


81 

Do. 


in 

1 A 

2 

2,100 

210 


420 

27 

7(X) 

2.2 



85 

Do. 

1 

2 

A 

2 J> 


250 

. 4 





92 

Do. 

*1 

fi 

2 7 


9<X) 

111 ) 

.9 


10-18 



2.5 


83 

Do. 

t3 

9 

3 

4 

2,250 

250 

.4 

1,000 

12 


1.8 

t0.51 

(t) 

104 

Do. 

5 

9 

1.8 

3 

1,500 

166 

.6 

500 

15-30 

300 

*2 

5 

3 

108 

Do. 

8 

10 

1.3 

4 





35 

1,200 

(9) 

*5 


U3 

Do. 













/ California crude oil. 9 Estimated at 0 gallons (?). See notes on Reply 100. 







































































































































































BRASS-FURNACE PRACTICE IN THE UNITED STATES 


(it 


Detail* of bran-melting practice in various types 

. (• DfsigntiU* estimated results rather than results base.I on average running conditions; 


31. HOUND, TILTING, OIL FURNACES, WITH HIGH- 


Reply No. 

Nature of plant. 

Height or shape of furnace. 

I 

!| 

-E 

S 

a 

Fuel and air supply. 

Analysis of 
charge. 

Composition of 
charge. 

Crucible maker’s No. 

Weight of charge. 

'5 

►» 

► 

6d 

o ° 

s 

00 

B. t. u. per pound 
or per cubic foot. 

Air pressure at 
burner. 

Pressure of fuel at 
burner. 

• 

3 

Q 

Zn. 

0 

CO 

• 

.fi 

fi* 

New metal. 

Heavy alloy. 

Light alloy. 

1 

2 

3 

4 

.Vi 

5ft 

5c 

5 d 

6 

7 

8 

9 



In. 

In. 


Per lb. 

Oz. 

Lbs. 

Pet. 

Pet. 

Pet. 

Pet. 

Pet. 

Pet. 

Pet. 


Lbs. 

30 

Mfe. 





00 

7.5 

75 

15 

5 

5 




OO 

1001 

61 

..do.. 



0.90 

(°) 

(*) 

( 6 ) 

67 

26 


7 

35 

45 

20 

125 

3jJ 

S3 

..do.. 

30 

36 

.91 

19,700 

20 

90 

(t) 

(t) 

(t) 


50 

45 

5 


.50ffl 

86 

. .do.. 



.88 



17-20 

Mn. 







600 

1 t son 









Hz. 









100 

..do.. 





16 

15 

Y. H. 







1 25 


117 

..do.. 


» • • • 

.84 


2J 

3-4 

58 

39 

* * • * 

3 

1 

50 


<*) 

7 i 


32. OPEN-FLAM K, TILTING, OIL FUR 


15 

Mfg. 

Spher¬ 

ical. 

.90 

19,000 

20 

15 

79 

9 

3 

9 

20 

40 

40 


650 





18 

Kef . 

_do... 





r. n. 






UN) 



r* 

Mfg. 

. .do.. 

.. .do... 

.87 

19,000 

16 

15 

87 

7 

3* 

24 

25 

55 

20 

15 


*00 

2*1 

Egg!... 

13 

15 

R. R. 


35 

50 


500 

31 

..do.. 

Cylin - 
drical. 

.87 

19,300 

14 

25 

87 





1,125 

6 

5 

4 

5 

85 

10 


39 

..do.. 

Spher¬ 

ical. 

.83 


8-16 

C) 

85 

750 






42 


.. .do... 

.87 


12 


R. B. 







9 750 


47 

Mfg. 

. 1". . 

_do... 



85 

5 

5 

5 

50 

50 


wo 

.500 

1,750 

54 

63 

.. .do... 



18 


SO 

7 

6 

7 

15 

5 

65 

55 

30 

40 


..do.. 

Egg.... 



12 

20 

88 

3 

5 

4 

/<T2,000 








\fl,000 

917 

65 

..do.. 

Spher¬ 

ical. 

.91 

19,500 

14 

30 

80 

.... 

10 

10 


60 

40 


750 






67 

. .do. . 

.. .do. .. 

.90 



10 

80 


10 

10 


(*) 

(*) 


000 

1,540 

812 

67 

..do.. 

_ do.. . 

.90 



10 

80 


10 

10 



73 

. .do. . 

Egg.... 

Spher¬ 

ical. 

.80 

19,400 

16 

40 

85 

.... 

1 

11 

3 




(t) 

78 

..do.. 

.90 






710 













80 

..do.. 

Egg.... 

Spher¬ 

ical. 

.87 

<0 

(0 

12 

30 

r. n. 





100 



.500 

80 

..do.. 

.87 

12 

30 

R. B. 





100 



700 












H 

81 

..do.. 

.. .do. .. 



14 

35 

w 

2 

10 

10 


10 

70 

30 


l,noo 

84 

..do.. 


.90 

It) 

12-15 

88 

2 



91 

..do.. 

Cylin¬ 

drical. 


18 

10 

85 

5 

5 

5 

45 

25 

30 


700 







92 

..do.. 

Spher¬ 

ical. 



10 

22 

R. B. 







9 750 

250 











96 

..do.. 

Egg.... 

.87 


11 

5i 

Pb. 




75 

15 

10 

(t) 

2,500 


Bz. 




156 

..do.. 

Spher¬ 

ical. 

.S7 

19,000 

8 

20 

88 

2 

10 






2,500 









169 

..do.. 

...do... 



32 

30 

85 

6 

6 

4 

45 

50 

60 

40 

35 

40 

40 

15 

15 


600 

174 

. .do.. 

...do_ 



12 

30 

K B. 





815 

175 

..do.. 




15 

35 

U. B. 





175 

..do.. 

Egg.... 



15 

35 

It. B. 




60 



* jmjj 

179 

..do.. 

.. .do... 



16 

75 

1 

9 

15 




185 

..do.. 

Rectan- 

.95 

18,000 

9 

20 

80J 

Hi 

7 

1 

5 

70 

25 




gular.f 









a Over 18,000 B. t. u. 
t> Steam atomization. 


* Special crucible. 
d Patched every 90 heats. 















































































































































DETAILED RESULTS OF INVESTIGATION 


65 


of furnaces and with various fuels — Continued. 

t indicates that notes on the reply number affect significance of figures so designated.1 
PRESSURE AIR, MELTING ITIGH-ZINC ALLOYS. 


Speed of melt ing. 

Life of crucible. 

Life of lining. 

Fuel consumption per cwt. 

of metal melted. 

Melting 

loss. 

Remarks. 

53 

Is 

s 

C/3 

W 

3 

o 

M 

Ilours per day. 

Ilours per heat. 

Furnaces per ten¬ 
der. 

Metal per furnace 
per day. 

Metal per furnace 
per hour. 

Time per cwt. of 
metal. 

Metal per tender 

per hour. 

Gross. 

Net. 

See notes on page 

Conditions of test, 

average or special. 

10 

11 

12 

13 

14 

15 

10 

17 

18 

19 

20 

21 

22 

23 

24 











Gals. 









Lbs. 

Lbs. 

Hrs. 

Lbs. 

Heats. 

IIts. 

oil. 

Pet. 

Pet. 



5 

10 

2 

10 

800 

80 

1.2 

800 

15-35 

900 

0.7- 

*1.5-1 


79 

Average. 











1.2? 





6 

8 

1.3 

1* 

1,800 

225 

0.45 

340 

43 

900 

1.8 

f5.6 


84 

Do. 

1 


(t) 

6 

500 




8 


5 

4 7 

t3 

92 

l>o. 

1 

8 

8? 

6 

1,800 

225 

6.45 

1,350? 



*2 


93 

Do. 

6 

9 

1.5 

3 

2.100 

230 

0.45 

690 

45-50 

<*1,800 


4 

3.5 

97 

Do. 

3 

8J 

2.8 

2 

2.200 

250 

0.4 

500 

20 

225 

2.5 

3.6 

2 

101 

Do. 


NACES MELTING LOW-ZINC ALLOYS. 


6 

9 

1.5 

2 

3,810 

425 

0.24 

850 


5,000 

2.89 

5.2 

17-6 

3.6 

74 

75 

Average 

Do. 

5 

9 

1.8 

l 

4.000 

444 

0.22 

444 


500 

3 

f5.4 

4.4 

ii 

Do. 


9 

1. 3 

4 

3, 500 

390 

0. 25 

195 



3.1 

4 

2.3 

79 

Do. 

5 

11* 

2.3 

2 

5,625 

490 

0.20 

980 


250 

3 

3.3 


80 

Do. 

4 

6 

1.5 

2 

500 

0.20 

1.000 


300 

2.9 

4-2.5 

3.5-2 

80 

Do. 

4 



1 

fl, 144 






4.4? 

4 

3.5 

81 

Do. 

y 

9 

1 

2 

4.500 

500 

O 20 1.000 


1,350 

2.2 

2 


81 

Do. 

10 

11J 

1.1 


5,000 

450 

0. 22 



6.000 

2.5 

+4 

+3 

83 

Do. 








600- 






4 

10 

2.5 

2 

7,000 

700 

0.14 

1.400 


800 

1 2.86 

\ Q 

9 7 

84 

Do 

6 

10 

1.7 

2 

5.500 

550 

0.18 

1,100 


' 1,200- 

1 2.48 

/ 3 













1,500 





4 

9 

2.2 

2 

3,000 

333 

0.30 

666 

. 

400-600 

1.4 

3 

1.5 

81 

Do. 

5 

9 

1. 8 


3.000 

333 

0.30 



900 

2.3 

3 

2.25 

84 

Do. 

.5 

9 

1.8 


7,800 

867 

0.12 



900 

2 

3 

2.25 

8. 

Do. 

4 

10 

2.5 

1 

3,250 

325 

0.31 

650 


1,200 

2.4 

5.2 

4.55 

86 

Do. 

6 

74 

1 3 


550 


0.18 




+4.8 

(t) 


86 

Do. 

4 

2 

8 

2 


2,000 

250 

0.40 



1.200 

2 

3 


90 

Do. 

4 

8 

2 


2,800 

350 

0.29 



2 

3 


90 

Do. 

3 

5 

1. 7 

2 

600 

0. 17 

1,200 


900 

1.7 

4 

2.5 

90 

Do. 





300- 




* 


2 

*5 

*4 

93 

Do. 





1,500 








2 



4 

9 

2 2 

21 

2 800 

311 

0.34 

780 


1,000 

3 



96 

Do. 

I5 

.0 

0 7 

1 

3 700 

370 

0. 27 

370 


400 

2.7 



96 

Do. 

6 

13 

2.1 

2 

15,000 

1,150 

0.09 

2,300 


900 

1.53 

4 

3 

97 

Do. 

2 

2 

1 



2,500 

0.04 



600 

4.5-3 


*3 

104 

Do. 

/+\ 

71 

1 2 

14 

3 600 

500 

0. 20 

750 


1,000 

2 

6 


107 

Do. 

\T) 

7 

* 2 
ft 

1 I 

1 J 

1 

5' 700 

710 

0.14 

710 

2 

(t) 


108 

Dc. 

ft 

Q 

1 8 

14 

10 000 

1 111 

0.09 

1.666 



2 

(t) 


108 

Do. 

fi 

o 

1 5 

3 000 

3,33 

0.30 




2 

2 


108 

Do. 

& 

10 

1 2 


10 060 

1.006 

0.10 



400 

2.9 

5 


108 

Do. 

2 

10? 

5? 

2 

3,250 

325? 

0.31 

750 


300 

1.2 

6.3 


109 

Do. 


t Over 20 pounds o Rated capacity. * Over 18,000 B. t. u. 

/Average. A “50 per cent scrap.” 


44712°—Bull. 73—16-5 










































































































































































6G BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


Detail* of brass-melting practice in various tyjxs 
(• Designates estimated results rather than results based on average running conditions; 

32. OPEN-FLAME. TILTING, OIL FURNACES 


Reply No. 

Nature of plant. 

Height or shape of furnace. 

Diameter or inside length 
of furnace. 

Fuel and air supply. 

Analysis of 
charge. 

Composit ion of 
charge. 

Crucible maker's No. 


Specific gravity of 
oil. 

13. t. a. per pound 
or per cubic foot. 

Air pressure at 
burner. 

Pressure of fuel at 

burner. 

Cu. 

s 

N 

c 

to 

Pb. 

3 

- 

£ 

it 

O 

• 

>> 

o 

£ 

2 

M 

•M 

Light alloy. 

Weight of charge. 

1 

2 

3 

4 

5a 

5b 

5c 

5<f 

6 

7 

8 

9 



In. 

7n. 


Per lb. 

Oz. 

Lbg. 

Pet. 

Pet. 

Pet. 

Pet. 

Pet. 

Pet. 

Pet. 


Lbt. 

1*7 

Mfiz 



19,300 

12 

40 

Pb 




70 

.30 



1 f 000 



5 • • • • 


Bz. 









1S8 

do 

Snhor. 

80 

19,000 

R 

90 

R B 




00 

• 40 



K,0 


*ieal. 












191 

..do.. 

■ • •do•*. 

.85 

19,500 

8 

20 

87 

6J 

3i 

3 

30 

40 

30 


1,000 

1 ‘Hi 

. do 

do . 






10 




75 

25 


700| 

204 

do 




8-10 

«3(?) 

R. 13. 





100 



1 f M6i 
















33. OPEN-FLAME, TILTING, OIL FUR 




Mfg. 

..do.. 

Spher¬ 

ical. 

.. .do... 


948 

5 8 

70 

2o! G 

4 

»j 65 

15 


3 


.0 9 

18 .... 



550 
















a Ounces. 









































































































































































DETAILED RESULTS OF INVESTIGATION 


67 


of furnaces and with various fuels —Continued. 

t indicates that notes on the reply number affect significance of figures so designated.] 
MELTING LOW-ZINC ALLOYS—Continued. 


Speed of melting. 

Life of crucible. 

Life of lining. 

Fuel consumption per cwt. 

of metal melted. 

Melting 

loss. 

Remarks. 

Heats per day. 

Hours per day. 

Hours per heat. 

Furnaces per ten¬ 
der. 

Metal per furnace 
per day. 

Metal per furnace 
per hour. 

Time per cwt. ol 

metal. 

Metal per tender 

per hour. 

Gross. 

Net. 

See notes on page 

Conditions of test, 

average or special. 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

O .) 

23 

24 











Gals. 









Lbs. 

Lbs. 

TTrs. 

Lbs. 

Heats. 

Hts. 

oil. 

Pet. 

Pet. 



7 

1 

1 

2 

7,000 

1,000 

0.10 

2,000 


875 

1.4 



110 


2 

2J 

1.15 

1 

1,740 

758 

0.12 

758 


450 

3.9 

f3.5 


111 

Do 

4 

~h 

1.8 

3 

6.600 

900 

0.11 

2,700 


500 

2 

3.6 


113 


5 

10 

2 

3 

3,500 

350 

0.50 

1.050 



1.5 

4. 5 


114 


6 

11 

1.8 

1 

10,000 

909 

0.11 

909 


1,040 

1-1.25 

t3 


116 

Do. 


NACES MELTING HIGII-ZINC ALLOYS. 


no 

10 

1 

2 

5,000 

500 

0.20 

1,000 


(ft) 

2.14 

1.4 

1.2 

70 

Average 











8 

7 


TO 

Do 

3 

5 

1.7 

2 


600 

0. 17 

1,200 


900 

6 

4 

on 

Dn 

3 

34 

1.1 

(?)6 


725 

0.13 

4,350? 


900 

3 

4 7 

t3 

QO 

fin 

3 

8 

2.7 

2,400 

300 

0.33 




10 

93 

Do 

3 

8 

2.7 

3 

1,800 

225 

0.45 

675 


1,350 

*2 

5 

2.5 

93 

Do. 

3 

8 

2.7 

1 

3,000 

375 

0.27 

375 



*2 

5 

2. 5 

93 

Do 

9 

9 

1 

2 

4,100 

45S 

0.22 

915 


1,350 

■ 3 


4. 7 

96 

Do 

6 

10 

1.7 

3 

1,500 

148 

0.68 

444 


650 

2.8 

*5 

*4 

97 

Do. 

f7 

10 

1.4 


4,250 

425 

0.23 



4,000 

3.2 

3.6 

2.2 

Qfi 

Do 

5 

9 

1.8 


12,.500 

1,390 

0.07 



750 


2 

10,8 

Do 

5 

10 

2 

14 

3,000 

300 

0. 33 

450 




10-12 


11 ° 

Do 










3.4 


113 

Do! 















NACES MELTING LOW-ZINC ALLOYS. 




0.7 




0.14 




© *— • 

5 

3.3 

3.5 

74 

80 

Average. 

Do. 





















NACES MELTING HIGII-ZINC ALLOYS. 


3 

10 

3.3 

1 

1,692 

170 

0. 59 

170 


750 

280 

6.2 

5.5 

74 

Special. 



1.3 



425 

0.23 




200- 

2.5-2.2 


‘Is 

Do. 











255 






b Lining not replaced in 24,000 heats, but repaired when necessary. 









































































































































































68 


bbass-furnace practice in the united states 


Details of brass-melting practice in various tyjxs 

('Designates estimated results rather than results based on average running conditions; 

3d. REVERBERATORY, OIL FUR 


o 

A 


c. 

- 

M 


79 


c 

A 

c. 


£ 

2 

a 

A 


Mfg. 


80 ..do.. 
82 I. 


? I 
£ 


JCS 

if 

« 


In. 


In. 


Fuel and air supply. 


o 

►» 

v 

N 

c 

i 

cc 


5a 


•o • 

S| 

Is 

• u 

cs © 


£ 


5b 


aS 


is 

< 


5c 


Ptrlb. Lbs 
0.91 19,250 27 


.87 19,000 

.95_ 


1 

15 


3 . 

w u 
£ 2 


Analysis of 
charge. 


5d 


c 

N 


C 

00 


£i 


Lbs. Pet. Pet. 
20 88 5 


20 R.B. 
fl40 R.B. 


Pet Pet. 

6 1 


Composition of 
charge. 


2 

o 

S 

i* 

«. 


>. 

o 

> 

t 


c 


§ 


/><*. 

None. 


Pet. 


00 


Pcf. 


o 

A 

m 

t 


A 


8 


20 . 000 ] 


o 

o 

£ 

B 


Lbs. 


4 , 

10 , 

4 , 


s 


37. REVERBERATORY, OIL Fl’R- 



ISO 

Mfe. 

..do.. 

(t) 

S3 




88 

2 

10 




None. 


10,000 
2,135 

202 

It) 




81 

8 

6 

5 


75 

25 











39. REVERBERATORY, SOFT-COAL FUR 


173 

Roll. 

8! 

$ 




00 

40L. 


80 

20. 


7,000 

180 

Mfg. 




Mn. 



100. 


10,000 




Bz. 

... 





180 

..do,. 

(t) 

(0 




Mn. 



100 



10,000 




Bz. 






a Over one-fourth; see notes on Reply 79. 
o 2 burners used. 


1 3 burners used, 
d All scrap. 






















































































































































DETAILED RESULTS OF INVESTIGATION 


69 


offurnaces and with various fuels —Continued. 

t Indicates that notes on the reply number affect significance of figures so designated.] 
NACES MELTING LOW-ZINC ALLOYS. 


Speed of melting. 

Life of crucible. 

Lile of lining. 

Fuel consumption per cwt. 

of metal melted. 

Melting 

loss. 

Remarks. 

Heats per day. 

Hours per day. 

Hours per heat. 

Furnaces per ten¬ 
der. 

Metal per furnace 
per day. 

Metal per furnace 
per hour. 

Time per cwt. of 
metal. 

Metal per tender 

per hour. 

Gross. 

Net. 

See notes on page 

Conditions of test, 

average or special. 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 











Gals. 









Lbs. 

Lbs. 

IIts. 

Lbs. 

Heats. 

Hts. 

oil. 

Pci. 

Pet. 



2 

7 

3.5 

(“) 

5 ,565 

800 

0.12 

200 


200 

1.11 

5 


87 

(6) 

2 

8 

4 

20,000 

2,500 

0. (M 




2.5-3 

5 


90 

( C ) 

1 

2* 

2.5 

* 

l' 600 

0.06 

530 


600 

1.25 

3.5 

. 

92 

Average. 


NACES MELTING HIGII-ZINC ALLOYS. 


1 

1 

4 

3 

6 

9 

3 

6 

2.2 

x 5 

9,000 

16,000 

4,666 

1,500 

1,777 

0.02 

0.07 

0.06 

2,333 

1,500 


1,100 

1.2 

1.28 

5 

3.6 

2 

3 

90 

92 

108 

(«) 

Average. 

NACES MELTING LOW-ZINC ALLOYS. 











Lbs. 

coal. 

2 

1 

2.5 

108 

115 

Average. 

Do. 

2 

10 

5 

1 

4,270 

427 

0.23 

. 427 


1,200 

88 

NACES MELTING HIGH-ZINC ALLOYS. 

2 

1 

1 

8 

4 

5 

4 

4 

5 

(t) 

i 

h 

14,000 

1,750 

2,500 

2,000 

0.06 

0.01 

0.05 

|520 

1,250 

1,000 

(t) 

(t) 

500 

(t) 

(t) 

50J 

18 

5 

4-3 


108 

108 

108 

Average. 

Do. 

Do. 


e 1 burner used. 9 Mechanical stoker; top and bottom blast. 

/ Air jet under grate. b Natural draft. 


























































































































70 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


NOTES. 

Reply 1 , subdivision IS .—Figures based on one div’ti run. Low-pressure uir con¬ 
sidered best. 

Rrply 2, subdivisions I and S3 .—A crucible lusts 18 heats on copper in the coke 
furnaces. 

The open-flame oil furnace has been run so as to give 26 heats of 500 pounds, or 
13,000 pounds of metal in 10J hours, the metal being taken away as fast as it is ready 
and recharging being done without delay. 

Fuel-oil tests: Flash test, 105° 0.; fire test, 110° C.; cold test, 4°t\; viscosity test, 
136 sec. at 40° C. (in Saybolt viscosimeter). 

The open-flame furnaces have not been relinod in eight years, but are patched at 
the end of the week. The charging hole and pouring spout are patched each morn¬ 
ing. The pouring spout has been reduced in size, the effort being to maintain a 
pressure considerably above atmospheric, with the idea that this may retard the 
volatilization of zinc. The open-flame furnace is capable of melting a large tonnage 
with a lower loss and less cost than the crucible or any other form of furnace. 

[The fuel and loss figures are based on complete and careful shop records and are 
probably reliable.] 

8PECIAL TEST. 

A special test was made to compare a natural-draft, pit, coke-fired, crucible furnace 
with a tilting, open-flame, oil-fired furnace as to melting loss. Several different alloys 
were used, the charge in both furnaces for each alloy being the same as to analysis 
and composition. 

Comjxiratiie results with coke furnace and with oil furnace. 


Alloy 

No. 


2 

3 

4 



7 


8 


Analysis. 


87 Cu, 5 Zn. 5 Sn. 3 Pb 
Red brass. 


Coke furnace. 

Oil furnace. 

Timeof 

Metal 

Metal 

Timeof 

Metal 

Metal 

Average 

heat. 

charged. 

lost. 

heat. 

charged. 

lost. 

metal 

loss. 

II. m. 

Pounds. 

Per cent. 

II. 

m. 

Pounds. 

Per cent. 

Per cent. 



1 1 

45 

1,003 

0.4 

0.7 




1 i 

20 

1,000 

1.0 

2 30 

212 

0.2 

1 

25 

1,000 

0.8 


3 45 

207 

7.0 

{? 

5 

30 

842 

840 

*>1 

6.3 

5.2 

3 30 

208 

15.0 i 

1 

35 

840 

7.3 

7.3 





55 

500 

1.2 


2 30 

250 

3.2 

1 

15 

.500 

2.3 

1.6 




1 

45 

538 

1.4 





1 

35 

000 

1.0 


4 00 

274 

0.9 

1 

0 

606 

1.8 

1.6 




1 

10 

587 

1.8 





2 

0 

1,459 

2.8 


3 30 

250 

3.3 

2 

0 

1,460 

3.8 

3.3 




1 

50 

1.220 

3.5 





1 

0 

722 

0.6 


2 30 

2.50 

1.6 

1 

5 

800 

1.1 

1.0 





45 

598 

1.3 1 





1 

20 

70S 

3.1 


45 

249 

0.6 

1 

0 

810 

2.3 | 

2.8 




1 

10 

803 

3.2 





1 

35 

800 

1.9 


3 30 

262 

1.2 

1 

5 

777 

1.7 

‘.7 




1 

30 

762 

1.5 1 


Total average loss in coke furnace. 3.42 per cent; in oil furnace, 2.48 per cent. 

Average output of metal from coke furnace, 81.6 pounds per hour; from oil furnace. 591 pounds per hour. 


Reply 3 t subdivision 16 .—When starting the operation of this pit type of oil furnace 
with low air pressure, the oil consumption ran about 2.7 gallons per hundredweight. 
Recently this figure has been reduced to about 1.7 gallons, the average being 2.2 
gallons. 


















































DETAILED RESULTS OF INVESTIGATION. 


71 


We have used at different times various types of both pit and tilting furnaces, fired 
with coke, coal, and oil fuel, and although the data on some of these furnaces are 
not available at the present time, the oil-fired furnace which is now in operation at 
our works we consider the best and most efficient that has come under our observation 
in an experience of over 30 years. 

Our metal losses are very small, the metal melted is first-class, the life of the 
crucible is greater than that of the coal or coke fired furnace, the melting time of the 
heat can be controlled, and after the first heat, when the furnace has warmed up, 
the heats following can be taken off in from 42 to 65 minutes, using Nos. 70 and 80 
crucibles and a metal mixture containing from 89 to 86 per cent of copper. 

Have used various types of furnaces and the old-fashioned coal or coke pit furnace 
gives very good results if the factor of time in melting is of no value and the metal 
is not allowed to “soak.” 

Of the oil furnaces that have come under our observation and have been used by 
us there are three types exclusive of the furnace being used at the present time. 

In the first (of the tilting type, of two makes) the metal was placed in a reservoir 
with the flame coming in direct contact with the metal. 

In the second style, which was also of the tilting type, the metal was melted in a 
large crucible, and when melted was poured into a second, or carrying, crucible to 
the flasks. 

The third was of the pit type without the combustion chamber. In this furnace 
the metal was poured into the flasks direct from the crucible in which it was melted. 

All three of the foregoing types of furnaces depended on compressed air to atomize 
the oil, thereby making an oxidizing flame and, as a consequence, a large percentage 
of shrinkage and bad castings. 

In the reservoir type of furnace, in which the flame came in direct contact with the 
metal, our experience was that really sound castings on which an internal test was 
required could not be produced, owing to the fact that the flame, coming in direct 
contact with the metal, burned out the alloys and made the metal hard; also to the 
fact that on being poured from the reservoir to the carrying crucible the metal became 
•xidized, volatilization set in, and a large proportion of bad castings resulted. 

For castings of the nature of gear-wheel blanks, housings, bearings, etc., we have 
no doubt that this type of furnace may give satisfaction. 

In the second type of furnace the pouring of the metal to the second, or carrying, 
crucible had the same effect on the metal as with the reservoir type. 

The third, or pit type, without the combustion chamber referred to above, gave fair 
but not entirely satisfactory results. This furnace, as were the two types preceding, 
was equipped with compressed air, causing an excess of oxygen in addition to the 
tearing and wearing away of both linings and crucibles. 

The roaring noise from several of this type of furnace in operation at the same time 
had a bad effect on the furnace men; it was a case of changing help continually. 

Would also state that it has been our lot to use a coke-fired tilting furnace of two 
makes, and we are free to say that the foundry making castings containing a number 
of cored passages and requiring an internal test of, say, 200 pounds steam pressure, 
would make no mistake in giving this type of furnace a wide berth. 

Our present installation of furnaces, equipped with the combustion chamber and 
burner of peculiar design, in which the oil is atomized mechanically by pressure from 
the oil pump, make our figures seem almost unbelievable. In a melt of 1,900,000 
pounds for six months, bad castings from both shop and foundry were 2.4 per cent. 

In this burner no compressed air is used; fan or blower air between 5 and 6 ounces is 
list'd just enough for complete combustion, so that when the atomized oil is forced 
through the incandescent combustion chamber the oil becomes a gas and attains its 
greatest heat as it enters the furnace proper, which is about on a line with the bottom 
of the crucible. 


72 


brasb-fubnace practice in the 


UNITED STATES. 


[The pinch type of tong* in unotl, but three sets of tonga ure kept, varying slightly in 
size, ho that an the crucible become*) smaller through use a pair in always at hand that 
titn the crucible properly. No squeezing of the |>ots by the tonga in allowed.] 

Reply 4, subdivision 11 .—Net Iohh of metal and fuel conaumption based on one day's 
run on No. 30 crucible. 

Percentage of melting Iohh in the same in all sizes of crucibles. 1.ohh on yellow brass 
in 2$ to 3 per cent. 

Per pound of metal melted, a No. 50 crucible will take about 10 per cent loss coal 
than a No. 30, and a No. 100 about 5 per cent less than a No. 30. The No. 100 does 
not increase in efficiency over the No. 30 as much as the No. 50 because of the thicker 
wall of fuel, which may be a little out of proportion. 

Reply 5, subdivision 22 .—At the beginning of 1913 we planned to replace this type 
of furnace by one burning coal, because of the high price and scarcity of oil, but have 
now (October, 1913) decided to keep the oil furnaces in operation for a while longer. 

The oil consumption is from a test made several years ago and is not guaranteed to 
be correct. 

The type of furnaces in the foundry was designed and built according to the ideas 
of the mechanical engineer and foundry foreman, both of whom are gone. 

The purpose of using small crucibles is to produce the small castings we make in our 
foundry, such as small trimmings, lock parts, etc. At times there is so much of this 
class that with large crucibles we could not pour fast enough at the proper tempera¬ 
ture. At the same time I realize that we can use, say No. (JO pots, to good advantage 
on our work in general, and the No. 35 on small work only, and we are using up a large 
stock that was on hand for some time before changing over to the larger size. 

I do not like this furnace for several other reasons. In the first place it requires two 
men to roll back the cover, which is made of brick in an iron frame, and, secondly, as 
we use a lot of sheet-brass scrap, borings, etc., it requires opening a number of times 
during a heat, and while this is being done, which takes about 8 minutes each 
(ime, the blast must be shut off, and the furnace, being wide open, rapidly cools and 
retards the heat. This constant cooling is also very detrimental to the life of cruci¬ 
bles. 

Reply 6, subdivision 13 .—Through the hole in the cover a feeder is placed, which 
is nothing more than the crucible that has performed its service in the jacket, and 
has been removed after melting 30 heats. A hole is put in the bottom of this crucible, 
and the charge is placed in it, the flames going up through the metal contained therein. 
The actual melting is really done in the feeder or hood as wo call it. The metal after 
liaving been melted in this way drops into the lower crucible, and is superheated. 

The crucible is worn out at 30 heats, and is used for the hood or feeder. Crucibles 
will average over 40 if run until worn out, and if the furnace is operated continuously 
they average 50. We have had individual crucibles run as high as 105. 

Gross melting losses are as follows: Yellow brass, 18.08 per cent; manganese bronze, 
3.38 per cent; leaded bearing bronzes, 4 to 5.50 per cent. 

The yellow brass here referred to is made largely from turnings and light brass. 
Manganese bronze is made from new metals. In remelting ingots this running loss 
would probably be less. The leaded bearing bronzes are made largely from scrap, 
turnings, etc. We have open-fiame furnaces at another plant, also have the old-style 
pit furnaces at both plants. We consider the forced-draft, tilting, coke furnace the 
most economical furnace, as regards operation, of any at present on the market, but it 
does not give good results for light work. The open-flame furnaces do not compare 
in economy with these. We do not consider this type of furnace very satisfactory for 
small castings. The old type of the pit furnace we consider gives the best results as 
regards quality—that is, gives the best physical tests, pressure tests, and the best 
behavior in the foundry. This superiority is accounted for briefly as follows: (1) 



DETAILED RESULTS OF INVESTIGATION. 


73 


Because the metal is cast direct from the crucible it need not be overheated to cast 
small work. (2) It is out of direct contact with fuel. 

We operated for quite a number of years a forced-draft, tilting, coke furnace that 
had a square jacket. We afterwards remodeled the furnace and designed a round 
jacket, with a consequent saving of 17 to 20 per cent in fuel. 

We do not know of any users of the forced-draft, tilting furnace who are using hard 
coal instead of coke. 

In our first experience with this furnace we used 72-hour coke mixed with anthra¬ 
cite coal. This practice we abandoned years ago, and are now using 48-hour coke 
exclusively, which works far better and is cheaper. The 48-hour coke gives a better 
flame and quicker combustion. 

Reply 7, subdivisions i, 27 .—Coke furnaces turn out a better grade of metal, with 
less shrinkage. On the gas furnace the loss on red metal is 4 to 6 per cent; on brass 
running 15 per cent or over in zinc the loss is 8 to 12 per cent. Coke furnaces are 
used almost entirely. 

Data on a special test using natural gas are given below. A pit furnace was rigged 
for gas and a test run on an alloy of 83 per cent copper, 7 per cent zinc, 4 per cent tin, 
and 6 per cent lead, the metal being poured into ingots. The test was run on parts 
of four different days. 

Results of special test with pit furnace using natural gas. 


Day. 

Length of 
heat. 

Gas used. 

Material 

charged. 

Charged. 

Recovered. 

Gross 

melting 

loss. 

Gas used 
per hun¬ 
dredweight. 


II. m. 

Cubic feet. 


Pounds. 

Pounds. 

Per cent. 

Cubic feet. 


1 8 

430 

Scrap. 

1S4 

172.5 

6.7 

•231 


1 5 

4:13 

Ingot. 

170 

167.5 

1.5 

254 


50 

353 

.. .cfo. 

174 



•203 


55 

429 

.. .do. 

163 



263 


50 

398 

.. .do. 

152 



264 

a 

1 18 

<>07 

Scrap. 

191.5 

187 

2.3 

318 


1 7 

469 

Ingot. 

189 

187 

1.05 

248 


53 

366 

.. .do. 

175 

170 

2.9 

•209 

a 

1 38 

713 

Scrap. 

152.5 

143 

6.2 

470 


52 

357 

Ingot. 

169.5 

166 

2.1 

211 


55 

409 

.. .do. 

168 



242 


i i 

477 

.. .do. 

157 



304 


i 

453 

.. .do. 

180 



252 


58 

444 

.. .do. 

173.5 



255 


57 

414 

.. .do. 

17n F> 



•236 








— 


l 

l 

l. 

l 

1. 
2 ' 

2. 
2 . 
3< 
3. 

3. 

4. 
4. 
4. 
4. 


a First heat with cold furnace. 

Average gross melting loss on scrap. 5.1 per cent; on ingot, 1.9 per cent. Average gas consumption, 264 
cubic feet per hundredweight. 

Reply 8, subdivisions 1 , 19 — A comparative test of the gross loss in melting red 
brass in 225-pound heats, three-fourths new metal, one-fourth gates, gave results as 
follows; 

Melting loss on red brass in two types of furnaces. 


Kind of furnace. 

Time of melt. 

Metal 

loss. 

— 


Hours. 

Per cent, 

til . 


1.54 

Hrt . 


1.65 



2.00 



2.48 





Plotting loss against time gives an almost straight-line relation between length of 
heat and percentage lost. The heats were slower than our regular practice. 











































































74 


BRASS-FURNAOB PRACTICE IN TIIK UNITED STATES. 


The testa were made by weighing the cold metal**, weighing the hot crucibles and 
metal and then weighing the empty hot crucibles after the metal had l»een poured. 

The crucible life is much better in iho coke furnace than in the oil. With oil at a 
reasonable figure, tho coke furnaces are on the whole the more expensive to operate. 

Reply 9, subdivision 1 . —[The gross loss of 4.2 per cent includes all losses on castings 
up to the time they are sold, and would bo leas on the basis of metal actually melted 
because the gates are remelted and because some of the loss occurs in grinding.] 
“Grab” tongs used. Crucibles last much longer than when pinched w'ith ordinary 
tongs. 

Reply 10, subdivision 28 .—Oil burner takes oil at 30-pounds pressure, and a little 
air for vaporization at 30-pounds pressure. Volume of air for combustion supplied 
through a concentric tube at 8 to 12 ounces. These furnaces are very quiet.* One 
can converse in ordinary tones while standing in the midst of a battery of them. 
They can be easily controlled so as to give a reducing flame. The oil and air are 
[•reheated by the Hue gases. The furnaces have not been relined since they were 
built, the only repairs being occasional face patching with carborundum fire sand 
when replacing crucibles. 

Although we do not use the open-flame furnace, just as good metal can be made 
with these, and even sound copper castings produced. 

Reply 11, subdivisions 8, 85. —Open-flame furnace is patched every day. It gives 
about 25 per cent loss on borings. The figures given are from a 22-day test. The 
coke furnaces are not used to any extent, most of the tonnage being from the open- 
flame gas furnaces. 

Reply 12, subdivisions 11, 85 .—One tender handles 3 gas and 7 coal furnaces. The loss 
t»n manganese bronze in gas furnaces is 6 per cent. Coal furnaces are relined three 
times in 14 months; covers and cast-iron flues every 6 months; gas furnaces once in 
12 months; covers and stool bricks renewed every 6 months. 

Crucible life is 18 to 23 heats in coal furnaces; 20 to 25 in gas, and then 3 to 5 more 
in coal furnaces. On account of difficulty of cleaning metal from bottom of gas fur¬ 
naces, we take no chances on a crucible cracking in them. There is practically no 
difference in the life of a No. GO and a No. 80 crucible. 

The gas furnaces supply a little cleaner metal with a slightly lower oxidation than 
the coal furnaces, but there is very little difference. 

Reply IS, subdivision 28 .—Oil consumption can not be given, as the furnaces are 
not metered, oil being used for other purposes beside melting. We also have pit fires 
[coke or coal, on which no data were given], the advantages of the oil furnace being a 
reduction in the c<xst of fuel and labor and better working conditions for the men. 

Reply 14, subdivisions 1, 16 .—The oil furnace is very good when operated by an 
intelligent man who is anxious to keep things clean and running smoothly. Other- 
wist', the bottom of the furnace gets clogged with slag and metal and hence the oil 
does not get proper access. Carbon and a smoky fire result, which slows up the 
furnace and makes a poor showing. Oil burner using oil under high pressure and air 
under low’ pressure is the best we ever tried, and we can get better results than with 
coke when the burner is operated properly in a clean furnace. For the average Polish 
furnace tender, the common, natural-draft, coke furnace with proper coke space 
produces the least all-around good results. For melting yellow brass, the coke furnace 
gives better results than the oil, owing to a somewhat slower fire and also owing to the 
fact that the men in puddling the brass are able to work over the coke fires better than 
over the hot oil fires. The metal must be poked down very frequently to prevent 
excessive zinc loss in refining borings. . 

Reply 15, subdivisions 24, 27, 82, 84 .—In our opinion both of the types of furnaces 
that w'e use have their advantages. The losses in the open-flame furnace are higher, 
but the fuel consumption and attendance is very low and the cost of crucibles is 
eliminated entirely. The slag from these* furnaces comes out in rather large matted 



DETAILED RESULTS OF INVESTIGATION. 


75 


pieces, but these we now successfully crush and recover the metal from them. We 
believe this type of furnace needs closer watching, but when operated with competent 
supervision we get very good results from the metal melted in it. The air on the gas 
furnaces is preheated by passing around the furnace, through a hollow casing, before 
going to the burner. Gas is seldom used on the open-flame furnaces. 

To show the effect of the speed of the heat on the loss of metal in melting, the follow¬ 
ing results of tests are submitted. Eight heats in the No. 125 gas furnace, starting in 
the morning or at noon after the furnace had cooled somewhat, averaged I hour 40 
minutes, with an average shrinkage of 1.97 per cent. Twelve heats after the first 
averaged 1 hour 9 minutes, and gave an average shrinkage of 1.12 per cent. The alloy 
was 87£ per cent copper, 5£ per cent zinc, 5£ per cent tin, H per cent lead, and the 
charge consisted of 300 pounds of clean gates. 

Records on 18 No. 50 crucibles in the pit gas furnace show an average life of 61 
heats, and on 86 No. 60 crucibles an average of 55 heats. These pots were pulled with 
the “grab” type of tongs. Eighteen No. 125 crucibles in the tilting gas furnace 
averaged 43 heats, and 11 No. 275 crucibles in the same type of furnace averaged 12i 
heats. Taking the crucible cost per pound of metal melted in the No. 50 as 100 per 
cent, the crucible cost in the other sizes was: No. 60, 123 per cent; No. 125, 173 per 
cent; No. 275, 705 per cent. 

Reply 16, subdivision 1 .—Our work is very light, 0.10 inch being the standard thick¬ 
ness, which makes it necessary for us to have a very hot metal and also for each molder 
to have a furnace from which to get his metal; therefore the oil furnace for our work 
was not very satisfactory. 

We have had a great amount of experience with oil furnaces; have tried out five 
different makes of same. We installed four different makes of the pit type, put them 
alongside of one another, and equipped each with a blower and a separate oil tank so 
as to get the exact amount of oil used and the pressure that was called for by the maker 
of the furnace. After the furnaces were installed we had a representative of each 
furnace company come to our plant and start his furnace; we were able to give the 
exact oil and air pressure required, and arranged the furnace to work just as the agent 
requested. 

After each furnace had been demonstrated and we thoroughly understood how they 
should be operated, we had each one overhauled, relined, and made as good as new. We 
then started the four on a three months’ test, comparing them with four coke furnaces 
working as nearly as possible under the same conditions in regard to the amount of 
metal required; we found that the coke furnace for our work was the best and cheapest. 
We had more trouble with our metal from the oil furnaces; our loss from spongy work 
was much greater. I believe this was greatly due to the fact that we could not keep 
our metal covered with charcoal, which caused more or less oxidation. Another 
condition which we discovered was that the greatest heat in the oil furnace was at 
the top of the crucible, which we have found is not in favor of a good metal and causes 
a great amount of oxidation. 

Although the actual cost of melting with oil was much cheaper, taking into account 
the loss in melt and the quality required for our work, coke melting is the cheapest in 

the end. 

We found it much more difficult for the melter to work oil furnaces than coke fur¬ 
naces. One of our oldest melters had the “brass shakes ” when operating these furnaces, 
something we have never had with coke. Although we could get more heat from an 
oil furnace, wecould not use the metal, and a great amount of oil was used in heating 
the furnace, which increased the cost of melting metal. 

SPECIAL TEST. 

A special test was made to compare four different oil-fired pit furnaces with a 
natural-draft, pit, coke-fired furnace. 


70 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


Red brass was the ulloy melted and the crucible used was No. 40. The result* 
follow: 

Results of melting red brass in four oil furnaces and one coke furnace. 


Item. 

OU 

No. 1. 

OU 

No. 2. 

OU 

No. 3. 

Oil 

No. 4. 

Coke. 

Metal molted in test. 

Malting time. 

Time per 100 pounds melted. 

Fuel per 100 pounds melted. 

Gross melting loss. 

.pounds.. 

.hours.. 

20.1130 
121.5 
0.59 
5. 80 
0.88 

17,007 

114.75 

0.07 

5.00 

0.03 

18.900 
123. 75 
(1.05 
0.0 
0.65 

21,727 
119.25 
0.55 | 
5.05 ' 
a 74 

19.450 
123.75 
0.64 
« 55 
a ho 


<* Pounds. 


The average net melting loss in the other coke furnaces in the foundry during thin 
test was 0.51 per cent. The linings were burnt out at the end of the test, whereas 
that of the coke furnace was in good condition. All of the furnaces were worked 
under the same conditions as with the regular coke furnaces. One or two more heats 
per day might have been taken from the oil furnaces, but only the amount needed in 
regular practice was taken out. There was thought to be a larger proportion of bad 
castings from the oil furnaces than from the coke. 

[This test is of interest in several ways. It shows that the loss on red brass can, by 
exercising care, be kept well under 1 per cent, either in coke or oil furnaces. It was 
considered to prove that the oil furnaces were inferior for the conditions in that foun¬ 
dry. It hardly seems, however, to have taken into consideration sufficiently the 
possible utilization of the speed of oil fuel. This foundry deals with very light cast¬ 
ings and requires extra hot metal. A separate furnace is run for each molder and the 
metal is held in the furnace until he is ready for it, even though the metal has been 
ready to pour previously. The coke furnaces in the test were run faster than the 
normal rate, as shown by the figures for reply Ifi in subdivision 1 of the table. The 
other replies in subdivision 1 lead to the belief that with a No. 00 crucible, even on 
work requiring such hot metal 40 pounds of coke per 100 pounds ot metal should be 
sufficient. The smaller crucible (No. 40) will give a lower fuel efficiency, and as 
hotter metal is required, the figure of 55 pounds per 100 shows a fair fuel efficiency 
for coke furnaces. The oil consumption shown in the tests, averaging 5.5 gallons, is 
high. The results presented in subdivisions 10 and 18 show that for a No. 00 crucible 
the normal figures run from 1.7 to 3.3 gallons. Allowing an increase in the ratio of 
40 to 55 over this figure of 3.3 gallons oil consumption, on account of the use of a smaller 
crucible and the need for hotter metal, the oil furnaces should not have taken over 
4.5 gallons per hundredweight at the outside, if run at full capacity.] 

Reply 17, subdivision 10 .—[In tabulating the pounds of metal per furnace tender 
per hour for rolling mills, it was impossible to keep the same basis of comparison as 
in foundries melting metal for sand easting. In such a foundry, the furnace tender 
seldom has anything to do with the metal after it has been taken from the lire; that is, 
after the pot has been pulled from a pit furnace or the metal poured into the ladle irom 
other types. The metal goes into the hands either of the molder and his helpor, who 
carry it to the molds by hand or by crane and pour off, or, in 411 increasing number of 
plants, of a “ pouring gang, ’’the members of which are trained in pouring and whose sole 
duty is to take the metal from the furnace tender, pour it, and return the crucible or 
ladle to the melting floor, thus allowing the molder to keep uninterruptedly at his work. 
The use of a pouring gang has met with some objection in shops operating under the 
piecework system, as it has been thought that the molder was thus held responsible 
for scrap caused by faulty pouring. The success reported by so many shops in the use 
of a pouring gang indicates that the objection is not serious, as scrap from faulty 
pouring is as a rule easily recognizable as such, and as the pouring gang soon become 




















DETAILED RESULTS OF INVESTIGATION. 77 

expert at pouring, it being easier to train a picked gang to pour than to train each 
individual molder, the scrap is less in the long run. 

In rolling mills the furnace tender, called the caster, has two, and sometimes three, 
helpers, and this gang handles in general from 8 to 10 fires, and makes four to five 
“ rounds” at a shift of about nine hours. Most rolling mills run double shifts, the fires 
being poked out at the end of each shift, on account of the accumulation of ash, the 
next shift building the fires anew. The caster and his helpers melt the metal, which 
is usually brought to them in trays, each tray with the proper charge of new metals 
and scrap for a single crucible, pour it into the iron molds, pull out the ingots or bil¬ 
lets, and dress the molds with oil. Hence in the tabulation of production in rolling- 
mill practice, “metal per furnace tender per hour” refers both to metal melted and 
metal poured into ingots, and not solely to metal melted, as in foundries in which 
sand castings are made. Most of the refining plants listed probably have the furnace 
tendex both melt and pour metal into ingot molds, though the data on this>detail are 
in most cases not clear.] 

Reply 18, subdivision 1 .—We have a draft sufficient to get out three heats of red 
metal in 10 hours, but we get out only two heats per day. We run the furnaces from 
7.30 to 11.15 and from 12.30 to 4.15. It takes 2\ bushels of coke to melt 100 pounds 
of metal. The proportion of different alloys melted is 70 per cent red bronze, 5 per 
cent yellow brass, 10 per cent manganese bronze, 10 per cent copper, 5 per cent 
miscellaneous. 

[Assuming 1 bushel of coke to weigh 40 pounds,® this would be equal to 90 pounds 
of coke per hundredweight of metal melted, the high fuel consumption being prob¬ 
ably due to the fact that the furnaces are not run to full capacity.] 

Reply 19, subdivisions 30, 32 .—The figures tabulated for gross and net metal losses 
are from very complete yearly records and cover running conditions. The results 
with two tilting oil furnaces with crucibles and with two open-flame oil furnaces are 
grouped together, as records are not available for each type separately. 

In two tests on the open-flame furnace, a 575-pound charge 85 per cent heavy 
alloyed material and 15 per cent borings was used. Analysis of the charge showed 87 
per cent copper, 7 per cent zinc, 3£ per cent tin, and 2£ per cent lead. The gross 
loss in melting was 2.43 per cent. 

With an 800-pound charge of the same alloy, consisting of 80 per cent of heavy alloyed 
material and 20 per cent of borings, the gross loss was 2.25 per cent. 

The average loss in tests throughout the year was 2.25 per cent. We have not 
been able to get any better results out of trials of the crucible oil furnace than from 
those with the open-flame furnace. In spite of the fact that many are against using 
a furnace in which the flame is played directly upon the material charged, we feel 
that these figures are a good thing to present and let other arguments rest. 

Reply 20, subdivision 18 .—We have five pit oil furnaces taking No. 70 crucibles, 
three pit oil furnaces taking No. 200 crucibles, two tilting oil furnaces taking No. 275 
crucibles, seven coke fires taking No. 70 crucibles, and six coke fires taking No. 250 
crucibles are used. One man can handle the five oil furnaces with No. 70 crucibles 
on brass and bronze. One man handles the three oil furnaces with No. 200 crucibles 
on manganese bronze, new metal, getting four heats in 11 to 12 hours from each fur¬ 
nace and sometimes an extra heat of scrap. Four men handle the 13 coke fires. No 
definite date on fuel consumption or metal loss are kept at present for the individual 
furnaces. 

No. 70 crucibles last 30 to 35 heats; No. 250, 19 to 23 heats. 

[The figures in subdivision 18 are on a test.] Under running conditions the per¬ 
centage of metal unaccounted for in the foundry is 4 to 4J; 1.5 per cent is recovered 
from refuse. The production consists of 40 per cent manganese bronze, 20 per cent 


« Wyer, 8. S., A treatise on producer gas and gas producers, 1901, p. 276. 





78 


BBA88-FURNACE PRACTICE IN THE UNITE!) STATES. 


white metal, and 40 per cent brass and bronze. We find the usual advantage* for 
oil -speed, better control, no coke or ashes to handle. We find on the oil furnace** 
that a furnace working under 10-ounce air pressure i* not *o good for high copper 
alloys as one working under 4-ounce pressure [high pressure on the oil]. 

For natural-draft coke furnaces the stack should be at least 90 feet high, and the 
area of cross section of the main flue should be 1J times the combined area of small 
flues. The cross-sectional area of the stack should be 1$ times the combined areas 
of small flues, a proportion contrary to boiler practice. 

Reply 21, subdivision 9— Not using our heats to the highest efficiency prolongs flu? 
life of the crucible. The variation in melting losses in refining yellow-brass borings 
to ingot is too great to allow’ its accurate determination. A “feeder" [old crucible 
with the bottom cut outl is set into the top of the meeting crucible and the borings 
fed into it. A cover or flux of gbss is used in melting. 

Reply 22, subdivision 11 .—The furnace has a diameter of 16 inches inside the lining. 
We have a special fire-tile lining made of four semicircular parts, the bottom circle 
being 4 inches thick and the top circle 3 inches thick. This gives the furnace interior 
a slight taper with the large diameter at the top. The furnaces are relined once 
every six months, but the lining is daubed with a mixture of fire clay and ground 
fire brick every morning. The grate bars are renewred about once a year. No other 
repairs are required. As we have a number of different mixtures, ranging from 90 
per cent copper and 10 per cent tin down to 60 per cent copper and 40 per cent zinc, 
running at the same time, w’ith no separate account kept of the losses of each mixture, 
w*e can give only an average from all of them, which varies in net loss from 1 to 6 per 
cent, depending upon the relative quantities of each mixture used. The average is 
about 3 per cent. 

In the oil-burning, tilting furnaces without crucibles w’e have found from experi¬ 
ments that the melting losses due to oxidation run at least 50 per cent higher than 
in the regular pit furnaces; the metal is not as clean nor as good; the double pouring 
necessary with a noncrucible furnace gives extra expense in keeping intermediate 
pots hot and higher melting loss on account of having to get metal hot enough to offset 
the extra cooling necessitated by the double pouring; and there is also danger of 
pouring steam metal too cold, with the result of greater percentage of leakage at the 
test pumps. Therefore we have discontinued the use of other than pit furnaces. 

Reply 2S , subdivision 7 .—We have made foundry tests on melting loss on our various 
mixtures and find that they run from an average of about 1.5 per cent in a high-grade 
red brass to about 5 per cent in yellow’ brass and manganese bronze. We of course 
recover the metal from our ashes and foundry sweepings, but distribution is not made 
in such a way that definite answers can be given. We have a number of standard 
mixtures, from a straight bronze containing 90 per cent copper and 10 per cent tin 
dowm to yellow brass and manganese bronze containing 30 to 40 per cent zinc. It 
is difficult to give an average. Our different mixtures are not run in separate fur¬ 
naces or under separate conditions except as each particular crucible requires it. 
We believe that metal melted in a crucible is better and cleaner than metal melted 
in those types of furnaces in which it comes in direct contact with the flame. Aside 
from this broad division of furnace types the experimenting we have done has not 
been sufficient to warrant definite conclusions. 

Reply 24, subdivision IS .—The proportion of sulphur in coke is 1 per cent; 72-hour 
washed coke is used. The coal moisture is 4 per cent; volatile matter, 5.5 per cent; 
fixed carbon, 77.5 per cent; and ash, 13 per cent. 

The “pinch” type of crucible tongs is used. 

Only one heat per day is taken. Eighty per cent of the fuel is coal on the bed, 
20 per cent is coke around the crucible. Natural draft is used most of the time, the 
forced draft being used the last hour of the heat. 





DETAILED RESULTS OF INVESTIGATION. 


79 


A fow trials were made to melt manganese bronze in an open-flame, tilting furnace. 
Oil fuel vaporized by air pressure was used. We found it impossible to control the 
loss of zinc, and consequently the physical tests showed erratic results from the melts 
made in that furnace. No trouble in this respect is experienced with the type of 
furnace used at the present time. 

Reply 25, subdivision 20— Sixteen pit and two tilting oil furnaces are used. The 
pit furnaces are 15 inches in diameter by 20 inches deep; eight furnaces per battery, 
two batteries in all. The pit furnaces in each battery are grouped two on each side 
of a rectangle. They were originally built for using coke and therefore had ash pits 
underneath. Fuel oil is now used instead. Practically no modification of the fur¬ 
naces was necessary to change from one to the other. The tilting furnaces are 15 
inches in diameter by 18 inches deep. Oil consumption is not known, as oil meters 
are unreliable and the oil used here is for forges, furnaces, riveters, etc. 

So far as we can determine, our furnaces give very satisfactory results. Oil fur¬ 
naces are better and more economical than coke for the reason that the furnaces may 
be heated in shorter time and that the fuel may be turned off immediately when 
the heat is completed, whereas much of the heat content of coke would be used 
when not required. [No data were furnished on tilting furnaces.] 

Reply 26, subdivisions 7, 13, 32. —A tilting coke furnace with air pressure of 4 to 5 
ounces is a good furnace for sensitive metals, such as yellow brass, manganese bronze, 
or red metals; this furnace does good work, as one melter can get out five or six heats 
out of nine hours’ work, with 400 to 500 pounds of metal to the heat. 

The crucible used in this furnace is 22 inches long, 14 inches at the top, running to 
about G inches at the bottom. A good crucible runs 50 to 60 heats, the cost of the 
crucible being $20. 

Our open-flame oil furnace is lined with silica fire brick; the cost is about $20; 
that is, lining and labor. This lining will last about two months. The openings 
on the furnaces have to be repaired every morning at a cost of 75 cents to $1. There 
are two oil burners, one in each end of the furnace, and from these we can get a very 
fine combustion in this furnace, but the melter must understand combustion. 
When this furnace is in proper order, it will give good results at a very small loss. 

We can not use this furnace to melt yellow brass or manganese bronze, as it blows 
all the zinc out, but we can melt all kinds of red metal in this furnace. It has an 
air pressure of 12 to 14 pounds; the oil pressure is about 15 pounds. We can get 
six or seven heats per 9-hour day, with about 500 pounds to the heat, with melter 
and helper. 

In the tilting crucible furnaces we find that a great deal of metal is melted from 
the top instead of from the bottom, which is detrimental to the metal. I have yet 
to find the first porous metal melted without a crucible in a rotary oil furnace. If a 
large quantity of metal is wanted, the oil furnace gets it out much quicker than the 
old-time crucible furnace; there might be a heavier percentage of loss in oil furnaces 
than in crucibles, but it depends a great deal on the metal being used. In melting 
in rotary oil furnaces it is well to have the furnace very hot before putting in metal. 

Reply 27, subdivision SO. —The furnace is run only about 10 days a year. 

Reply 28, subdivision 28. —The oil pressure is secured by forcing air at 70 to 75 
pounds on top of the oil tank. Can push the furnaces and get four heats per day. 
A glass slag or cover is used on the metal. The crucible block has two V-shaped 
depressions at right angles to allow some heating of the bottom of the crucible. 
Tilting furnaces are better than pit furnaces. 

Reply 29, subdivision 7. —Furnaces repaired every 125 heats. 

Reply 30, subdivision 3. —A No. GO crucible tilting furnace and a No. 40 furnace 
are used. The oil pressure is about 75 pounds; the air pressure about GO pounds. 
Crucible life is 15 to 35 heats, according to annealing of crucible. Good flux will 
save metal and so will good furnace tender. 


80 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


Old-time coal furnace turns out better metal all around. [A No. 00 tilting furnace 
is uncommon. The maker of the oil burner used usually supplies one taking a pres¬ 
sure of 30 pounds on the oil and 2 pounds or less on the air. An inquiry us to the cor¬ 
rectness of the figures on oil and air pressure, metal loss, and oil consumption was 
unanswered. The metal-loss and fuel-consumption figures are evidently only esti¬ 
mates.] 

Reply 31, subdivisions 32, 34. —Figures on gross melting loss include all foundry 
losses as well as mere melting losses. [No separate figures given for gas and oil ] The 
oil furnaces are not pushed to the limit, as with a hot furnace a heat can be gotten out 
in 45 minutes. 

Reply 32, subdivision 2. —Pit furnace preferred. 

Reply SS, subdivision 2. —We have no experience with other than coke furnaces. 

We liave no record of our percentage of loss during melting, as we do not keep any 
routine foundry records of daily heats. Our square furnaces are all of the one size, 
and require about the same amount of coke to charge a furnace for a No. 80 pot as for a 
No. 125 pot, minus the amount of space taken up by the larger pot; consequently we 
melt a No. 125 pot of metal cheaper than we do a No. 80 pot. 

Reply 34, subdivisions 1, 28. —We are getting an average of about 19 heats from the 
No. 275 crucibles in the oil furnaces, and anywhere from 19 to 30 heats, depending on 
the make of crucible, from the No. 70 crucibles in the t-oke furnaces. From our point 
of view, as to the relative advantages and disadvantages in the two types of furnaces, 
much might depend upon the relative cost of fuel oil and coke, but thus far we find 
the quality of metal melted in the oil furnaces as good in every respect as that obtained 
from the pit furnaces. Our oil furnaces liave been installed for a period of only about 
six iveeks. 

On the oil furnaces, starting with the cold furnace, the first heat in the morning this 
furnace will consume about 3$ gallons per hundredweight of metal; that is, red brass, 
containing 85 per cent copper, 5 per cent tin, 5 per cent lead, and 5 per cent zinc. 
The second heat will consume about 2J gallons, whereas the third and remaining h(»ats 
consume about 2.28 gallons per 100 pounds of metal melted. 

Reply 36, subdivision 4■ —(See remarks as to furnace tenders in notes on Reply 17.J 

We liave tried oil as a fuel, but find tliat the life of the crucible is very much less— 
so much so tliat we consider the use of oil inadvisable, especially since the price of 
fuel oil lias increased so materially. 

Reply 37, subdivision SO. —Our melt is about one-half red brass, one-quarter yellow 
brass, and one-quarter German silver. Fuel and loss figures are on all alloys, no sepa¬ 
rate records being available. We started out using a high air pressure on our oil 
burner and git much better results by reducing the pressure. With our present oil 
pressure and present type of burner, our air pressure is about as low as we can go. 

The crucible life depends on the make of crucible. Our records show a life of 1 to 
GO heats. 

Reply 38, subdivision 2. —On 9 furnaces natural draft is used, with stacks 95 feet 
high and 30 inches inside diameter. 

We liave tried open-flame oil furnaces, crucible oil furnaces, and forced-draft, tilt¬ 
ing, coke furnaces, and find that the pit fires give the best results in physical and * 
hydraulic tests. 

Reply 39, subdivision 32 .“In our oil furnaces, the oil is forced by compressed air at 
20 to 50 pounds; the blast is furnished by a low-pressure blower. 

Our furnaces run three hours in the morning and three in the afternoon. We could 
get six or eight heats if necessary. Physically, there is little difference between 
metal from the open-flame furnaces and from others. Chemically, we find tliat we 
must use a crucible to g*t exact results. 

We use 4.1 gallons of oil per hundredweight of finished brass castings. We also melt 
iron in this type of furnace, the melting ratio being 8.2 gallons per hundredweight of 


DETAILED RESULTS OF INVESTIGATION. 


81 


finished castings. The amount of oil to melt the charge will be 25 to 30 per cent less, 
as this amount goes back as gates and sprues. This is not our best practice on this 
furnace, as we had some trouble during the month for which these figures are taken 
with poor oil and inexperienced furnace men. 

Reply 40, subdivision 16. —We also use pit coke furnaces, with which one furnace 
tender can handle two to seven furnaces. We use 35 pounds of 72-hour Connellsville 
coke per hundredweight of melt. 

The net loss on yellow metal is about 10 per cent. 

Oil furnaces are more rapid than coal or coke, and not as much labor is required. 

[This reply w r as noted on the question sheet and was returned without address, 
hence no inquiry could be made for more detailed information.] 

Reply 41, subdivision 14 .—Furnace should be lined every two months. There is 
no difference in the quality of metal from this and other types of furnace if the metal 
is not overheated. 

Reply 42, subdivision 32. —This reply was noted on the question sheet and was 
returned without address; hence the small charge, which amounts to 286 pounds, or 
about 35 per cent of the rated capacity of the furnace, and the high oil consumption, 
could not be verified. | 

Reply 43, subdivision 30 .—The gross metal loss in melting is 6 to 5 per cent on cast¬ 
ings. Allowing for remelt of gates, the loss on the charge itself is about 3 per cent. 

An oil furnace in which the flame does not come in contact with the metal is much 
better than one in which it does. We have tried and discarded an open-flame furnace. 

We are increasing our melting capacity, but are putting in new coal furnaces instead 
of oil furnaces, because of the high price of oil and the uncertainty of delivery. 

Reply 44, subdivision 19. —[This reply was noted on the question sheet and was 
returned without address; hence more detailed information could not be requested.] 

Reply 43, subdivision 16. —We have had as high as 54 heats from a No. 80 crucible. 
There is considerable recovery from slag, etc., but our records do not allow figuring 
this back to the original melt. Pit furnace, coke-fired, still used with No. 40 crucibles 
for certain work. Yellow brass and other light work. Unless ventilation is good, 
pit coke furnaces are the best. Oil furnaces cause sickness. 

[Oil consumption given as 23 to 26 gallons per furnace per day; 2,400 pounds melted 
per day, or an oil consumption of 0.96 to 1.09 gallons per hundredweight of metal. 
A request for verification was unanswered.] 

Reply 46, subdivision 5.— We get four heats per day per furnace. We could run six heats 
but do not need to do so, as our furnace capacity is more than required. The compo¬ 
sition of our melt varies greatly on account of many mixtures used. Ordinary red 
brass is 85 per cent copper, 5 per cent tin, 5 per cent lead, and 5 per cent zinc. We 
use probably 35 per cent of gates. It is impossible to give accurate melting losses, as 
we do quite a lot of pigging up. Our total melting loss will average 4 to 5 pe- cent. 

Our yellow brass is made entirely from scrap yellow brass, with the addition of 
5 per cent of lead and 10 per cent of copper where necessary. We do not keep melting 
loss separate on red and yellow brass. 

Have used only gas and oil furnaces outside of coke, and neither can compare to coke 
for our class of work, which is small castings almost entirely. Oil furnaces are exceed- 
ingly good for heavy red brass but not good for yellow. Gas furnaces cause greater 
loss and cost more than coke. Do not know about quality of metal, but any furnace 
that gives great loss by oxidation owing to excessive blast can not make good metal 
that has to stand pressure test. 

Reply 47, subdivision 32. —We have other kinds of furnaces at our foundry, but the 
greater part of our work is done with the open-flame furnaces, and they are the only 
ones in connection with which we have made a series of tests. The other types are 
used only occasionally. The advantage of the open-flame furnace is the short time 
taken to melt and the fact that no crucibles are used. 


44712°—Bull. 73—16-6 



82 


BRASS-KURNACK PRACTICE IN THE UNITED STATES. 


Reply 46, subdivision 1. -One-fifth of our tonnage is on yellow the fuel and lo*» 

figures for which an* included. On yellow brass, using 20 per cent of borings, our 
groan loan is 7 per cent. We have just installed a forced-draft tilting coke furnace for 
making ingot from Istrings, but do not yet feel safe in using this on our regular work. 

Reply 46, subdivision 7. —We have six sizes of furnaces, with dimensions as follows: 


Inside diam¬ 
eter. 

Height. 

Thickness of 
brick. 

Inch tt r. 

Inches. 

Inches. 

13 

25 

3 

14 

28 

3 

15 

31 

3 

16 

31 

3 

17 

31 

3 

20 

31J 

3 


Sizes given are the sizes of the lining; outside of this lining is the sheet-iron drum. 
The lower half of the lining consists of a grout, made of carborundum fire sand, fire 
clay, old fire brick, and some salt. 

The crucibles used range from No. 35 to No. 200. 

One furnace tender can take care of 8 to 10 furnaces. We figure 100 pounds 
of coal to melt metal equivalent to 100 pounds of finished castings. 

We get four heats per day on furnaces up to No. 100. These average three heats per 
day. Furnaces larger than this do not run regularly. 

We have no data as to the frequency of relining furnaces. We have found this 
need to vary greatly, depending upon how the furnaces are forced. We have had as 
wide variations between relinings as 3 to 15 months. Minor repairs are made as needed 
but no record kept. 

We average about 35 heats per crucible, sometimes running up as high as 40 to 42 
on a No. GO crucible. 

We determine the net percentage by melting a given quantity of metal and pouring 
it in ingot form, thus eliminating all wastes and shop losses other than the loss by 
volatilization. losses determined in this way average 3 per cent on new’ material, 
5 per cent on all scrap material, and 8 to 10 per cent on all turnings. We find it 
possible to melt copj>er alone with no appreciable loss. 

With our foundry running entirely on jobbing work, as it is, we have comparatively 
small opportunity forgathering data on furnaces except in a general way. The large 
number of alloys running and the irregularity in the heats is principally what compels 
us to adhere to the old style of pit furnaces, as they afford us more latitude for short 
heats, quick changes, etc. 

Reply 50, subdivision 19. —Gravity feed system on oil from 60-gallon tank through 
f-inch feed pipe. 

Reply 51, subdivision 1 . —Each molder tends his ow r n furnace. 

Crucible life averages 34 heats; sometimes runs as high as GO, but very seldom. 

The only other furnace we have had experience with is an oil furnace. We found 
that unsatisfactory because it gave out such dense zinc fumes that our men got the 
‘‘shakes. ” 

We also melt yellow brass. Fuel and loss figures include both red and yellow brass. 

Reply 52, subdivision 16. —Analyses of oil: Flash, 180° F.; fire, 270° F.; cold, 25° F.; 
viscosity, 96 seconds at 100° F. 

. Find no difference as to the quality of metal, whether melted in coke or in oil 
furnaces. Main advantage of oil furnaces over coke is the saving in labor and cost of 
fuel. However, the cost of fuel in the oil furnaces is offset to a great extent by the 
additional cost of power required to run the blower. We have no way of judging the 
relative fuel consumption in our large and small furnaces. Twenty No. 45 crucibles 










DETAILED RESULTS OF INVESTIGATION. 


83 


averaged 21.1 heats; maximum 31, minimum 14. Twenty No. 70 crucibles averaged 
18.2 heats; maximum 24, minimum 14. 

Reply 53, subdivision 1 . —[This reply was noted on the question sheets and was 
returned without address; hence no more detailed figures could be obtained.] 

Reply 54, subdivisions 16, 28, 32. —Our total melt runs 2 or 3 tons per day—about 
2,500 pounds of No. 12 aluminum ingot, about 2,000 pounds of composition ingot 
brass, about 500 pounds of copper, tin, lead, and zinc (new metals), and possibly 
1,000 pounds of borings, gates, and sprues. 

We believe our melting loss averages about 3 per cent. 

We consider the open-flame furnace a good furnace where large quantities of metal 
must be melted rapidly but do not consider it economical or conducive to a high grade 
of metal, etc. 

We consider the crucible oil furnace a very good furnace, as regards the quality of 
metal and economy of operation, etc.; in fact we consider it the best on the market 
to-day; in the past six years we have made three separate trials of such furnaces in 
three different plants. 

We are unable to give you definite information on the consumption of oil in the 
different furnaces, as we do not meter the furnaces separately. Our impression is 
that crucible furnaces are more economical as regards oil than open-flame furnaces, 
possibly from 15 to 20 per cent. 

We believe that the No. 125 crucible is a great deal more economical than the No. GO, 
as both furnaces have the same burner, and it does not take a great deal more oil to 
melt the 350 pounds in the No. 125 than it takes to melt the 100 pounds in the No. (H). 

The melting loss in the No. 125and in the No. 100 crucible is about the same, averaging • 
probably 3 to 3J per cent, whereas the open-flame furnace averages 31 to 41 per cent. 

Reply 55, subdivision 27 .—Shape of our two furnaces, cylindrical; of two sizes: 
Outside diameters, 34 and 33 inches; heights, 33 and 28 inches. 

Lining—fire clay, of two thicknesses: 2J and 1J inches. 

Gas used is from wells on company’s property; it is not metered. Number of heats, 

4 on aluminum, 2 on brass. 

Furnaces relined once a year and repaired whenever necessary. 

IIeats to life of crucible, 10 on brass, 40 on aluminum. 

We melt aluminum, red brass, manganese bronze, and gear bronze, all consisting 
of about 75 per cent new metal (including gates) and 25 per cent of old metal. 

Reply 56, subdivision 11 .—Our experience covers furnaces using three kinds of fuel, 
namely, anthracite coal, coke, and crude oil. 

As far as results are concerned, the only reason we give preference to furnaces using 
anthracite coal over furnaces using coke is because the former occupy much less room, 
a consideration of vital importance in our location. Our experiences with furnaces 
using crude oil were very unsatisfactory for two reasons: 

First, because of the fumes from the oil itself. Our foundry has excellent venti¬ 
lation, but in spite of this, we seem unable to force the fumes or vapor from the 
foundry room. 

Second, our business is such that we are required to produce alloys of very accurate 
proportions, and in most instances we found it impossible to do this with the crude- 
oil furnaces. An alloy containing a certain proportion of tin or zinc could not be 
maintained, owing to the fact that the flames from the oil burner seemed to burn out 
the tin or zinc and to melt the copper only. 

Reply 58, subdivision 21 .—Out furnace holds two No. 35 crucibles. The capacity 
is three heats in 10 hours, but we seldom run more than two. The furnace is square; 
inside dimensions about 4 by 4 feet by 3 inches; fire-brick lining. W e use only one side. 
We get about 650 pounds per day, melting gates; 350 pounds, melting borings; have 
only one furnace. [Data not clear.] 


84 


BRAS8-FURNACE PRACTICE IN THE UNITED STATES. 


Reply 60, subdivision 17. —Eighty-font chimney on 16 furnaces. One melter ia 
taking cart* of 15 furnaces with a helper part of the time. The watchman starts the 
fires. 

We find that we have leas trouble with crucible metal than with any other. Open- 
flame furnaces also used; with a careful furnace tender we can get a* good metal from 
these as from pit furnaces. The castings from metal melted in the open-flame fur¬ 
naces stand up as well on hydraulic test. [No data on open-flame furnaces.] Open- 
flame furnaces used chiefly for ingoting scrap. Have to have 12-ounce air pressure 
on open-flame furnaces to get the metal out in a reasonable time. “Grab’' tongs are 
used. 

Reply 61, subdh'isions 17, 31. —Ix>ss figures are lumped for coal and oil and for red 
and yellow brass. Had castings are apt to be slightly higher from the coal than from 
the oil furnaces. Oil furnaces with the burner above, pointing downward into a 
combustion chamber, are somewhat better than those fired from the bottom. Oil 
vaporized by steam at the burner. 

In one typo of furnace a No. 125 crucible lasts 45 heats; in another, in which the 
crucible is not supported at the bottom, it lasts 42. Oil-furnace figures lumped for 
both types. 

Reply 62, subdivision 12. —We have tried a gas furnace, but found that we would 
have to have gas for not over 30 cents per 1,000 cubic feet, whereas our city gas costs 
$1 per 1.000 cubic feet. We also have found that our metal loss is considerably greater 
from oxidation, and therefore have gone back to our pit furnaces. 

Reply 63, subdivisions 13, 28, 32 .—Castings made from metal melted in crucible 
furnaces show a slight superiority on both physical and pressure tests. There is no 
apparent difference as to behavior in foundry, although tilting furnaces without 
crucibles show a higher melting loss and a larger percentage of defective castings, 
owing to oxidation. They are more economical because of the low cost of lining as 
compared with the cost of crucibles. 

The reason that we get a lower fuel efficiency out of the larger open-flame furnace 
than from ihe smaller furnace is that the average charge in the large furnace is not as 
near to the full capacity as in the small furnace; for example, the average charge for 
the large furnace of 2,000-pound capacity is 1,750 pounds, four heats being run in one 
day, and for the small furnace of 1,000-pound capacity the average charge is 917 
pounds, six heats per day being run. 

Reply 64. subdivision 1 .—We use principally scrap, consisting in a large part of 
yellow brass; one furnace tender can handle only five furnaces, and then by no means 
easily. 

Our gross loss on both red and yellow brass (yellow brass is 65 per cent copper, 30 
per cent zinc, and 5 per cent lead) is 9 to 10 per cent; the net loss is about 5 per cent; 
it is not determined accurately. On red metal the average net loss is close to 3 per cent. 

Reply 66. subdivisions 2, 32. —[In reply to an inquiry as to the low figure for oil con¬ 
sumption, this firm replied: “We find that the figures given you for oil consumption 
are correct and should stand, as they represent what we are actually doing every 
working day under normal conditions.”] 

Reply 67, subdivisions 31, 32. —Open-flame furnaces are patched every day. The 
furnaces are the same size for the No. .40 and the No. 80 crucibles, and there is but 
slight variation in the amount of coke used for the No. 40 and the No. 80. 

Reply 68, subdivision 6.—Our metal must needs be heated to a high temperature in 
order that it may be carried in the crucibles to the various molds, as we are able to 
pour as many as 36 molds from one No. 35 crucible of metal on some of our light jobs. 
We use a furnace designed by ourselves which utilizes the wa^te heat in the primary 
furnace as it passes through a secondary chamber on the way to the flue. In this 
secondary chamber we can run down to a molten condition two charges of rod brass 
and sometimes four charges of yellow brass, while we are bringing up the metal in thv 





DETAILED RESULTS OF INVESTIGATION. 


85 


primary fire to the necessary pouring temperature. The primary furnace is 4} feet 
deep, and lined up square, 14 inches in diameter, with fire brick about 9 inches 
between the fire space and the steel shell of the furnace. The ash pit is closed so as 
to give a forced draft under the grate bar. 

We have tried three types of oil furnaces: First, an open furnace, which we did not 
like on account of the great amount of fumes thrown out in the foundry and on account 
of the effect of the flame coming in direct contact with the metal, which apparently 
so affected it that it would not run in our small light castings. We next tried a portable 
oil-burning furnace, supposed to move around the foundry on a track. This furnace 
was so constructed that the crucible was not removable and the flame came in contact 
with the metal as it did in the ordinary open-flame iumace; the results were about 
the same. We also experimented with a stationary oil-burning furnace in which the 
crucible was removable, but each time came back to the coal and coke burning 
furnaces. 

[A special tall crucible 9£ inches in diameter and 17 inches high is used. The 
metal is poured very hot, almost at the boiling point. The furnace tender pokes the 
metal with an iron rod, and not until he can feel the metal “jump” when stirred is 
it considered ready to pour. The castings are so light that there are 2 pounds of metal 
in gates and sprues to 1 pound of castings. A thick fuel bed is used. Both coke and 
coal are used, but it was stated that coal alone would probably give better results, 
although the cost would be higher. The furnaces had been built round, but have 
lately been rebuilt in square form. The fuel consumption in the square form was 
stated to be considerably greater per hundredweight of melt than in the round fur¬ 
nace. The difference was ascribed to the employment of a less careful furnace tender. 
The square form was built mainly because the operator wished to use a form of tongs 
having trunnions that fit into bearings on the pouring shank, so that the metal car¬ 
riers can stand upright while the molder tips the crucible to pour the metal. The 
projecting trunnions on these tongs would not allow their use in the round furnaces.] 

Reply 69, subdivision 80 .—Oil furnaces, as compared with coke furnaces, have a 
greater output, require less labor and attention and less room, use cheaper fuel, and 
are cleaner. Their disadvantage is that they bum out the zinc; consequently we 
have to add 2 pounds of zinc to every 300 pounds of metal. 

Reply 70, subdivision 2— Loss figures include red and yellow brass. Loss on yellow 
brass runs from 10 to 5 per cent in refining borings. 

Square furnaces are used to give room for tongs. 

We have never tried the other improved furnaces but have watched with interest 
the experiences of others and have never found their results to have been sufficiently 
successful to warrant our making a change from the old-style pit furnace, as we have 
always found the metal made in this way to be of a better quality in every direction. 

Reply 71, subdivision 7 .—We are using the pit furnace. Have used a tilting oil 
furnace with crucible and open-flame oil furnaces. We found from actual test that 
the crucible pit furnace answered our purpose much better, as we can handle the 
metal to better advantage as to temperature and shrinkage. 

The net percentage of loss on yellow brass, with an average analysis of 67 per cent 
copper, 30 per cent zinc, and 3 per cent lead, is about 4 per cent. 

We have tried several makes of furnaces, including the crucible tilting oil fur¬ 
nace, and two forms of open-flame furnaces. Our experience has been that the open- 
flame furnaces can be handled very successfully on composition mixtures, but on 
yellow brass we did not have such good results. We have also found that the operator 
is a very important feature in successfully running these furnaces. The crucible, 
tilting, oil furnace gave fair results, but on account of the excessive cost of fuel oil 
we found the crucible pit furnace was better suited to our requirements. 

Reply 72, subdivision 2. —We use pit coke furnaces, but from our experience we 
believe that on our class of work the best results can be obtained from either a gas 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


86 

or un oil furnace of the crucible type, preferably arranged for tilting, a* on thin tyj>e 
of furnace the melting loss in lowered; it is more simple to get material at a proper heat, 
the li.'e of the crucible is much longer, and attendance is leas; although we can find 
no difference in the quality of the metal either on physical or pressure test. 

We are herewith inclosing a copy of our daily melting sheet, which is a fair example 
of the way our melt runs. 

[In this day *8 run, with 55 per cent of new metal, 30 per cent of borings, and 15 
per cent of gates, the gross loss was 3.5 per cent. On yellow brass (70 per cent copper, 
30 ]>er cent zinc), with one-third each of ingot, gates, and borings, the gross loss was 
9.4 per cent. The fuel consumption on the total melt, of which 55 per cent was yel¬ 
low and 45 per cent red brass, averaged 69 pounds of coke per hundredweight of 
melt, or 50 percent more than was given in the body of the report as the average figure.] 

Reply 7.1, subdivision 32. —This furnace has two egg-shaped chambers placed end 
to end. The figures given consider both chambers as one furnace. 

Metal from the open-flame oil furnace is as good as from a coke-fired crucible. 

Reply 74, subdivisions 2, 4. —Square furnaces are used to make room for tongs. 
Gross inciting losses: Gun metal 1 per cent, red brass 1$ per cent, half yellow and 
half red brass 2 per cent, yellow brass and manganese 2£ to 3 per cent. 

Oil furnaces have been tried and discarded. The forced-draft tilting coke furnaces 
give the same quality of metal, but the melting loss is higher, although the coke con¬ 
sumption is lower than in natural-draft coke furnaces. Most forms of tilting coke 
furnaces stand so high in the air as to make charging and coking hard on the furnace 
tender. 

Reply 7.5, subdivisions 1, 16. —We use two grades of metal: Yellow brass consisting 
of 2 parts of copper to 1 of zinc, and red brass consisting of 82 to 85 per cent of copj>er, 
4 per cent of tin, and the balance zinc and lead. The loss figures cover both, as separate 
figures are not available. 

At the present price of fuel oil it is somewhat cheaper to melt by coke than it is 
by oil, but on the other hand we can get out a good deal more metal with oil. We 
have not found any difference in quality of metal. 

We <1 id not find the burner supplied with our oil furnaces satisfactory and have 
changed to one using low-pressure air and high-pressure oil. 

Reply 76, subdivision 1 .—[Fuel and loss figures are rough approximations and not 
based on records.] 

Reply 77, subdivision 1 .—[The accuracy of the fuel and loss figures is doubtful. 
During a visit to this plant by the author the foreman stated that the fuel consump¬ 
tion was 70 to 85 pounds of coke per hundredweight.] 

Reply 78, subdivisions 3, 28, 32. —The open-flame furnace is seldom used and then 
only in an emergency. It was used for one entire day in the last tw r o months; the 
furnace received a chaige of 710 pounds of “compo” braas, and a loss of about 140 
pounds resulted. The advantages of melting brass in oil-burning furnaces has been 
questioned by numerous foundry men, and I am of the opinion that circumstances, 
locality, nearness to the fuel markets, and transportation facilities have a peculiar 
bearing on this matter, but aside from that I am sure the best results in making steam- 
tight work has been by the use of coke-burning furnaces. 

The oil furnaces melt quicker in some respects but only in the melting of light 
M eompo” or brass have they equaled the coke furnaces. It is cheaper to melt with 
coke than oil, when you consider the extra cost of piping and the heavy loss of crucibles. 

Our oil furnaces are not giving the results anticipated when they were installed. 
The coke furnaces have proved their superiority over oil-burning furnaces in making 
steam-tight work, such as high-pressure valves, condenser heads, etc. 

Probably under a fan-blower system instead of high-pressure air the results from the 
oil furnaces may be more satisfactory than at the present time. No pressure tests 
have been made, but a number of physical tests have been made to make compari- 


DETAILED RESULTS OF INVESTIGATION. 


87 

sons and decisions. No appreciable difference in the tensile strength or the bearing 
qualities of each metal. [On a visit to this plant it was found that the oil burners 
in use did not properly vaporize the oil and admitted too large a volume of air in the 
effort to vaporize it, giving an oxidizing flame. Moreover, in the crucible furnace the 
flame was pointed directly at the base of the crucible and the oxidizing nature of the 
flame cut away the crucible, causing the low life. The burners on the open-flame 
furnace are in similar shape and have not been run under proper oil and air pressure. 
This will at least partly account for the poor showing of the oil furnace.] 

Reply 79, subdivisions 8, 18, 15, 28, 32 .—The metal (68 per cent of copper and 32 per 
cent of zinc) from the square, tilting, forced-draft, coke furnace is poured into a ladle 
and then into a slab or billet mold, 40 by 144 by If inches, at about 1,850° to 1,900° F. 
Analysis shows an average zinc loss during melting of not over 0.5 per cent. 

The advantages of the natural-draft furnaces over other furnaces used at this plant 
are the quality of metal produced, the small melting losses, and the carrying off of 
obnoxious gasses; these gases are carried through the stack, thus relieving the shop 
of a great deal of the obnoxious fumes that would otherwise be spread, causing great 
inconvenience to the workmen. A furnace man has greater opportunities to watch 
his metal and to see that it is at all times covered with charcoal, thus shielding it 
from oxidation. 

One of the disadvantages (if it is a disadvantage) is the length of time required to 
run a heat down. The cost of fuel may be slightly higher, but when consideration 
is given to the amount of metal produced in one day by one furnace man and a helper, 
in comparison with that produced by other furnaces used here, it is not so high. 

It is true that other furnaces get a greater number of heats per crucible. If the 
crucibles of the natural-draft furnaces were treated in the same manner as those of 
the other furnaces, probably there would be a greater number of heats per crucible; 
these crucibles after being used all day are dumped on the floor and are allowed to 
cool in the temperature of the shop; they are not put back into the furnace and allowed 
to cool off gradually with the furnace, as the crucibles of the coke and oil furnaces 
are allowed to do. 

Another great advantage of the natural-draft furnaces is the small space a batter}’ 
would occupy in comparison with the oil or coke furnaces. In the shops where 
large bronze castings are made—that, is, castings weighing 10,000 to 17,000 pounds 
or more—it would be almost impossible to use the coke or oil furnace, owing to the 
space a batten' large enough to melt sufficient metal to pour the casting would occupy. 

In all probability the forced-draft coke furnace is the next best, as far as the quality 
of the metal and economy in fuel are concerned. The heat can be run down in a very 
short space of time, making this class of furnace good to follow up a molding machine 
on some classes of work. 

One advantage it has over the natural-draft furnace is the small amount of ashes 
to be cleaned out. It seems to consume nearly all the fuel. 

One of the disadvantages is the obnoxious gases that are thrown out into the shop. 
Another is that the furnace man is not able to keep a good watch on his metal; also 
the furnace does not bring down the metal hot enough to pour all classes of work 
without recoking the furnace; when tins is done, it has no advantage over the natural- 
draft furnace as to time required to run a heat down. These furnaces are hard on 
the furnace man. lie is not protected at all from the heat emitted from the furnace 
while he is recoking it. On account of the forced draft the wear and tear on the 
crucible and lining is slightly greater than that of the natural-draft furnace. 

The oil furnace has the advantage over the other furnaces that it is easier to handle, 
requiring very little attention; there are no ashes to handle and no cost for removing 
ashes. The furnace is not hard on the furnace man; he is protected from the heat 
at all times. In charging the furnace, he has only to shove the ingot of copper into 
the crucible as these ingots arc laid on top of the furnace. One of the disad vantages 


88 


BRASS-PUBNACE PRACTICE IN THE UNITED STATES. 


is the obnoxious gas tnat is thrown out into the shop; another is the roaring noise tluit 
is made by the blower. The cost of fuel is higher than with the coke furnace, making 
the cost of production a little greater tlian with the coke furnace. 

The cutting of the crucible aud lining are greater tlian with the coke furnace, as 
the pressure is greater. 

In regard to the fuel efficiency of the large coal-fired pit furnaces being less tlian 
that of the smaller ones, the loss of efficiency of the largo furnace was probably duo 
to the condition of the furnace. Doth furnaces wore in poor condition and in need 
of repairs. There was not time to put these furnaces in first-class condition for the 
tests; the two used were taken at random from a battery of 10. It is thought 
that both furnaces would have made a much better showing had they been in first- 
class condition. The tests were made as if they were on the regular work. There 
were no special efforts made. 

The shape of these furnaces, whether round or square, is a matter of opinion; some 
claim the circular furnace is the better of the two; both have their advantages and 
disadvantages. The square furnaces have been used in our foundry a number of 
years with good results. It is true they require more fuel than the circular furnace 
and probably the heat is not quite as regular as in the circular furnace. Some claim 
that the pocket in each corner of the square furnace is an advantage in that it is much 
easier to place the tongs on the crucible to remove it from the furnace. The fire 
is much easier “chunked down” in a square furnace. The circular furnace does 
not require as much fuel, and the heat appears to be more even. The foundry’ here 
had no experience with the circular furnace, owing to the fact that the square furnaces 
have always proved satisfactory and have always yielded good results. 

Shape and dimensions of the reverberatory oil furnace for melting scrap are as follows: 
Tliis furnace is oblong, 4 feet 6 inches wide, 8 feet long, and 7 feet 6 inches high. 
The melting chamber is lined with fire brick. It Ls 13 inches high from the bottom 
of the furnace to the crowm, at the charging end. It is 3 feet 4 inches high and 3 
feet wide at the back end. The runner is 0.21 inch from the floor line to the bottom 
of the runner. The metal is charged at the front end, and the tapping-out hole is 
located on the side. 

This reverberatory furnace is a standard make with a rated capacity of 2,000 pounds. 
We overcliarge it about 50 per cent. There are two burners used, with an air pres¬ 
sure of 27 pounds per square inch. The furnace is charged with heavy scrap; the 
turnings and skimmings are charged from time to time until the full amount of the 
charge is in the furnace. The furnace is preheated about one and a half hours before 
the charge of metal is placed. The second heat is charged while the furnace is still 
hot. About two and a half hours is required for the first heat and about two hours 
for the second heat. Between the first and second heats, the time required for charg¬ 
ing and making ready is about one hour. The time required from the time the furnace 
is lighted until tlie end of the last heat is seven hours. 

We reline tliis furnace on an average of once in 11 months. It is run almost con¬ 
stantly, being run for four months, two heats per day, then shut dowrn for three 
w T eeks or a month. The average number of heats per lining is 200. 

It does not require the entire time of four men to handle this furnace. The furnace- 
man cares for the furnace and has everything in readiness for the helpers to charge the 
furnace. It requires two helpers to charge the furnace and the other helper is used to 
help pour off, when the metal is down. It requires about 15 minutes to pig the metal. 

(As an example of a complete report of a comparative test, the following from Reply 
79 is presented:] 





DETAILED RESULTS OF INVESTIGATION. 


89 


Details of practice with five types offurnaces in a given foundry. 


Item. 

Large, 
natural- 
draft, coal 
furnace. 

Small, 
natural- 
draft, coal 
furnace. 

Crucible, 
tilting, oil 
furnace. 

Crucible, , 
tilting, 
forced-draft 
coke 

furnace, j 

Reverber¬ 
atory oil 
furnace 
with two 
burners. 

Diameter or inside dimensions. 

31X31 

27X27 

34 

36 ! 

54X96 

Height, inches. 

43 

36 

27* 

32 

79 

Thickness of fire-brick lining, inches. 

41 

41 

4 

5 

& 

Kind of cover. 

Cast iron. 

Cast iron. 

Fire brick. 

Fire brick 


Diameter or dimensions of cover, inches... 

25X25 

22X22 

274 

32 1 


Depth of covers, inches. 

3J 

4 

3 

4 


Thickness of fire-brick lining of covers, 





inches. 

2 

2 

3 

4 


Size of flue, inches. 

8X10 

7X7 




Height of ash pit, inches. 

24 

19 


19 


Width of ash pit, inches. 

22 

20 

1 

32 


Length of ashpif, inches. 

42 

27 




Size of crucible used. 

No. 200 

No. 80 

No. 275 

No. 225 


Life of crucible, number of heats. 

12 

16 

22 

21 


Moisture in fuel, per cent. 

4.16 

4. 16 




Volatile matter in fuel, per cent. 

3.10 

3. 10 


2.50 


Ash in fuel, per cent.. # .t. 

10.57 

10.57 


11.50 


Sulphur in fuel, per cent. 




0.9 


Specific gravity of fuel. 



0.9105 


0.9105 

Analysis of fuel, °B. 



24 


24 

Analysis of fuel; B. t. u. per pound. 

12,060 

12,960 

a 19,350 

12,750 

a 19,350 

Fuel used. 

Egg coal. 

Egg coal. 

Crude oil. 

Coke. 

Crude oil. 

Blast pressure. 



20 ounces. 

/2 inches of 

J-27 pounds. 





\ water. 

Heats run before relining furnaces. 

300 

450 



200 

Length of working day pier furnace, hours.. 

7 

7 

73 

7i 

7 

Total metal charged per furnace, pounds... 

1113.5 

724 

3228.5 

3016.5 

6505 

Nature of charge. 

New metal. 

New metal. 

New metal. 

New metal. 

Scrap. 

Metal loss per day, pounds. 

6.75 


134 

19J 

3284 

(iross losses, per cent. 

0.61 

0.62 

0. 42 

0.64 

5 

Copper in metal charged, per cent. 

90 

90 

90 

90 

88 

Tin in metal charged, per cent. 

7 

7 

7 

7 

5.5 

Zinc in metal charged, per cent. 

3 

3 

3 

3 

5.0 

Lead in metal charged, per cent. 



1.55 

1.55 

1.5 

Elastic limit of alloy produced. 

16,807 

14,769 

14,769 

15,278 


Tensile strength of alfoy produced. 

47' 798 

42;883 

42i831 

42', 831 


TCInnpatinn of allov nroduufid. dpt cent.. 

65.90 

30.58 

34. 70 

20.05 


Tfpd notion of allov nrodneed. dot cent..... 

64.24 

34.40 

35.36 

24.31 


Number of heats. 

2 

3 

5 

5 

2 

Metal charged in first heat, pounds. 

556. 75 

251.5 

711 

611 

3,740 

Metal charged in second heat, pounds. 

556.75 

251.5 

702.5 

600.5 

2,825 

Mot n.1 charred in third heat, Hounds. 


221 

704.5 

600 





710.5 

605.25 





400 

600 


Total metal charged per day, pounds. 

1,113.5 

724 

3,228.5 

3,016.75 

6,565 

Losses in first heat, pounds. 

3.5 

1.25 

3 

4 

187 

Losses in second heat, pounds. 

3.25 

1.50 

2.75 

4.5 

141.5 

I .dqcpq in third heat noiinds 


1.75 

2.75 

3 


f.nccoQin fourth heat "Hounds. 



3 

3.25 


f.ncQPQ in fifth heat nonnds. 



2 

4.5 


Total losses per day, pounds. 

6. 75 

4.5 

13.5 

19.25 

328.5 

Fuel used in first heat, pounds or gallons.. 

250 

100 

19.75 

213 

41.6 

Fuel used in second heat, pounds or gallons. 

144 

51 

12.5 

113 

31.4 

l?nol ucpd in third heat. Hounds or Pillions 


53 

11 

107 





11 

118 


I?i,nl naad in fifth hont Hounds or Pftllnns 



7.75 

130 


Total fuel used per day, pounds or gallons.. 

394 

203 

62 

681 

73 

Metal melted per pound or per gallon of 






fuel, pounds . 

2.8 

3.1 

52.1 

4. 43 

90 

Average time of first heat, minutes. 

b 181 
c 1S3 

b 132 
<•87 

b 120 
c 78 

b 106 
<•70 




114 

69 

64 





72 

70 


\ trorniro fimn of fifth hortt TT1 iH111AS 



45 

68 



2 

2 


3 


Averace metal per minute, pounds. 

3.04 

2.17 

8.4 

7.97 

15.63 

Number of furnaces one lurnaceman can 






attend . 

8 

10 

2 

2 

1 

Metal produced, pounds . 

8,908 

7,240 

6,457 

6,033 

6,565 


a 145,600 B. t. u. per gallon. 


t> Furnace cold at start. 


c Furnace hot at start. 






































































































































90 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


(The above results show again that the lonaes on gun metal from new material can. 
with care, be kept below 1 per cent. The results of this teat are cited in full, because 
of ita completeness— measurement of the draft on the natural-draft furnaces, analysis 
of the flue gases, and measurement of tile temperature to which the metal was h«*at«*d, 
being about the only omitted details that W'ould have given useful information.] 

Reply SO , subdivisions 7, 32, 37 .—The reverberatory furnace ia 8 feet 8 inches long 
by 5 feet 8 inches wide, 3 feet 4 inches high at the aides, and 4 feet high at the center 
(inside measurements]. The furnace ia lined with fire brick to a thickness of 1 f<*ot 
4 inches on the walla and 9 inches thick at the door end. It has a sliding oval-shaped 
door, 3 feet 8 inches by 2 feet 4 inches and 5} inches thick, made of cast iron and lined 
with fire brick 3$ inches thick. 

In this furnace the oil is under a pressure of 20 pounds, and three burners, furniah«*d 
by the maker of the furnace, are used. The air pressure ia supplied by a pressure 
blower at a pressure of 1G ounces. The furnace ia used only occasionally, and then 
only for large castings. It takes three men about 1$ hours to charge it; after that one 
man handles it. 

The furnace uses between 2$ and 3 gallons of oil to 1 hundredweight of brass melted. 
"This is on a single heat from a cold furnace and would be reduced if the furnace were 
in constant use. 

Both the open-flame and the reverberatory furnaces are usually allowed to cool 
down for an hour or so at the end of 4 hours’ melting in order to preserve the lining. 
The furnace is so seldom used that no accurate data can be given as to the length of 
time the furnace may run without relining. 

The furnace is rated at 10 tons, but to date it has never been necessary to make any¬ 
thing larger than a 5-ton casting from this furnace in one melting. Gates, sprues, br¬ 
ings, and other scrap, are used whenever the nature of the casting will permit, the 
amount of new metal being kept down to the minimum. Compositions are made 
according to requirements. 

Metal melted in a crucible furnace gives the best tests. In connection with the 
metal melted in the reverberatory furnace, in which, owing to the air blast, it is not 
always possible to make a reducing flame, at times considerable oxidation of the cast¬ 
ings has resulted. 

The loss in the two makes of open-flame furnaces on yellow-brass scrap is 5 per cent. 
The pit furnaces are intended for a Xo. GO crucible; No. 25 and Xo. 100 crucibles are 
sometimes used. 

Eight thousand pounds of red-brass borings was run down in a cupola usually used 
for iron. Four hundred pounds of coke was used on the bed, then the borings, with 
960 pounds of coke in the charge. A very mild blast was put on for 1$ hours, after 
which the metal was poured into ingots. Seventeen pounds of coke per hundred¬ 
weight of borings was used. The metal loss was 8 to 10 per cent. There seemed to 
be no trouble due to absorption of sulphur from the coke, though no analysis of the 
metal was made for sulphur. With the addition of 25 per cent of new metal, the ingots 
were satisfactorily used for making pump castings. 

Reply 81 , subdivisions 32 , 83 , 38 .—The crucible furnace is a safe one as far as the 
metal is concerned, but for our work is entirely too slow. 

We will take a No. 150 crucible, put it in the pit fire, and it will take anywhere from 
2$ to 3 hours and the loss runs from 3 to 4 per cent. Now take the space for coke and 
the extra labor of handling the same as well as the loss of crucibles. From experience 
we find the open-flame furnace far ahead. We can melt 1,000 pounds of red or yellow 
brass in one hour with 30 gallons of oil, where in the pit we would use about 600 pounds 
of coke and would require the extra handling of ashes after heat was drawn. The dis¬ 
advantage of the egg-shaped, open-flame furnace is that it throws the fumes and gases 
into the shop and is detrimental to the health of the men. The lining is a little trouble¬ 
some. Owing to the shape and position, the overhang is apt to fall in once in a while, 


DETAILED RESULTS OF INVESTIGATION. 


91 


but for speed in melting and keeping the metal in good condition, I consider the fur¬ 
nace excellent for general work. 

The spherical, tilting furnace is worked on the same principle as the egg-shaped 
one. Its advantages over that are the better lining; that is, it stands up better; being 
of brick it consumes a little more oil and is not so fast. 

When we want first-class valve metal, we always use this type of furnace. We have 
tried all our furnaces on tests of some kind, but we found the open-flame furnace the 
best for pressure tests, such as valves from one-fourth inch to 10 inches. We tried 
a forced-draft, tilting, coke furnace, with crucible. We had the same man who now 
runs our spherical, open-flame furnace run it for 7 hours, 6 heats, 400 pounds each 
heat, but he was a very tired man. With the open-flame furnace lie can take out 
3,000 pounds in 5 hours and feel in good condition at the end of the day’s work. 

One good point about the spherical, open-flame furnace is that it does not blow the 
fumes out into the shop. Owing to its shape and position, the long pouring spout 
can be kept under the hood at all times. Another great advantage the oil furnace 
shows over the crucible and pit furnaces is that there is some assurance of getting 
your metal when you want it. From experience, we can tell how long it will take to 
melt a certain amount, whereas the pot of a crucible often leaks when you are ready 
to pour. I consider the oil furnace the cheapest as regards the physical condition of 
the metal. I have seen tests taken from crucible metal which did not compare with 
the oil-furnace product. No matter how you melt, whether in oil furnace or crucibles, 
if the pouring is not done at the proper temperature, the alloy will be poor, as each 
alloy requires different treatment and to be poured at different temperatures to suit 
the class of work in hand. 

Our reverberatory furnace is oil fired. It has an oblong furnace door 11 feet wide, 
13 feet long. It has a 7-ton capacity. The walls are of fire brick, 24 inches thick; the 
floor is a layer of brick covered with 1 inch of foundry sand wet with clay water, and is 
cleaned for each different alloy. The door is 4 feet 6 inches by 3 feet 6 inches, with a 
small door in the center, 13 by 18 inches for charging turnings, of cast-iron lined with 
brick. Three low-pressure air burners are used, high-pressure burners having been 
discarded. 

One furnace man with a helper is required. This furnace is used for melting down 
miscellaneous scrap. It has not been relined in 3 years. We use a sand floor for 
each different alloy. Fourteen thousand pounds is melted per heat. Miscellaneous 
scrap and about 20 per cent borings is the composition of the melt. Red brass, yellow 
brass, manganese bronze, and liigh-tin bronze, as well as general sera]) for ingots, are 
produced from this furnace. It melted 000 tons of different alloys without repairs 
to brickwork. 

The reverberatory fuel-oil furnace compared with the natural-draft, coal furnace, 
shows up way ahead in all respects. Over half the time, labor, fuel, and floor space is 
saved. 

We will take a heat of 10,000 pounds, consisting of 50 per cent of heavy scrap, 30 
per cent of light scrap, and 20 per cent of borings, tapped in 1,000-pound lots and 
poured into ingots for analysis. Three hours will be consumed from the time of 
starting to the finish of work. One furnace man and a helper can look after this heat, the 
charge being put in the furnace the day before the melt. In a case of this kind the 
heavy metal is put in the furnace when it is cold, so that the larger door may be re¬ 
moved, as we oftentimes put in a piece weighing 1,500 pounds, which must be handled 
with bars. When the heavy charge is melted, the borings are shoveled in through 
the small door and pushed into the bath. 

This furnace has run since July, 1909 [reply dated Nov. 27, 1912], and melted GOO 
tons of all kinds of compositions for ingots and large castings, such as circulating 
pumps, main condensers, and gear wheels, which show well on tests. The only 
repairs made to date consisted in the making of sand floors about 1J inches deep. 


92 


BKA88-FURNACE PRACTICE IN THE UNITED .STATES. 


In the case of the natural-draft furnace there are the grate bars to be replaced, the 
ashes to be removed, and the floor of about 2 inches of Hand to be made-up. If JOO 
tons of alloy were melted in this furnace it would be ill bad shape, whereas tho oil 
furnace is very well braced by stay Isilts and metal sheathing. 

A great advantage of oil furnaces is that when fluxing you can put the flux in the 
bottom of the ladle and then pour the metal, which then mixes better than with the 
crucible, in which there is a great loss because the flux has to be pushed through the 
metal, as in the use of phosphorus. 

Reply 8', suMivisions 1 , 2 8, 37 .—We burn Connellsville coke, for which detailed 
analyses are not available, and natural-draft furnaces, vacuum not known, are used. 
The stack is 84 feet high and 31 inches inside diameter; it accommodates 19 pit furnaces. 

For ordinary brass-foundry work the pit furnace is far superior to the tilting or rever¬ 
beratory furnace. The losses are small and therefore the quality of the product more 
uniform and reliable. With care and skillful operation the product of the reverbera¬ 
tory furnace is as reliable as that from the pit furnaces. The greater time element 
for the pit furnace is not a serious objection. For running down turnings and miscel¬ 
laneous scrap the pit furnace is superior. 

Our reverberatory fuel-oil brass furnace is rectangular in horizontal plan, being 
7 feet wide and 9 feet long, shallow at the rear and deep at the front; roof arched from 
side to side and also from front to rear; tapped from the front into a pit. Lining, fire 
brick, G inches thick, with sand bottom. 

Entire front face removable for extensive repairs; door with peek hole in remova¬ 
ble section; cast-iron sections bolted together and lifted in one piece; lined with 
fire brick. Specifications state that oil shall have a specific gravity not greater than 
0.94G5 (18° 11.) at 60° F.; the oil pressure is 15 pounds and the air pressure 140 pounds 
at the throttle. Patent burners of the high-pressure closed type are used. It takes 
one man a full day, or two men two hours, to charge. 

This furnace is used almost entirely for running down scrap, such as large castings 
or tubing; for this class of work it is excellent. In one case where analyses were made 
of a large propeller that was run down, zinc was added to make up for the volatiliza¬ 
tion ; there was no difference in t he analyses before and after such addition. 

As to our tilting oil furnace with crucible, the data are based on less tlian a dozen 
heats. The only advantage of tliis type of furnace is the rapid melting which may be 
obtained. These furnaces have not been used for two years. 

Reply 83, subdivisions 4, 31, 33, 38 .—The natural-draft pit furnaces used Lehigh 
anthracite coal of best quality, clean, dry, and free from slate, bone, dirt, pyrites, 
and other impurities, and Connellsville 72-hour coke of the following analysis: 
Specific gravity 1.8, or not less than 1.75; moisture 0.42 per cent, not to exceed 1 per 
cent; volatile matter 0.80 per cent, not to exceed 1J per cent; fixed carbon 87.46 per 
cent, not less than 86 per cent; ash 11.32 per cent, not to exceed 13 per cent; sulphur 
0.69 per cent, not to exceed 0.80 per cent; phosphorus 0.015 per cent, not to exceed 
0.03 per cent. 

The draft is estimated to be about 0.25 inch of water. 

The answers aside from those for the reverberatory are based on the regular output 
of brazing metal, gun bronze, aluminum zinc, Muntz metal, scrap brass, white metal, 
naval brass, manganese bronze, and various other special compositions. The losses 
are lumped for all alloys on all the furnaces aside from the reverberatory. 

The coal and coke j)it furnaces and the crucible oil furnaces are used for all work 
requiring special physical cliaracteristics and pressure test. The open flame is used 
for yellow brass and small fittings. The reverberatory is used for heavy manganese 
bronze castings. 

Satisfactory metal can be produced from either the coal and coke or the oil crucible 
furnaces, tno coal and coke furnace showing the highest efficiency in operation and a 
more uniform product. The crucible oil furnace is used as a reserve in case it is necca- 


DETAILED RESULTS OF INVESTIGATION. 


93 


sary to reline the pit furnaces or make repairs on the stack. It is hard on crucibles, 
and losses are considered to be somewhat higher than in the case of pit furnaces. A 
heat in the crucible oil furnace takes six hours with cold furnace and three hours with 
heated furnace. In the open-flame furnace it takes one and one-half hours with cold 
furnace and one hour with heated furnace. The reverberatory takes six hours with 
cold furnace. The losses in melting in the other furnaces are comparatively small 
compared with that with the open-flame furnace, in which the flame comes in direct 
contact with the melt. In the case of yellow brass and manganese bronze, the losses 
in the open-flame furnace are largely due to the volatilization of the zinc. 

A test on the reverberatory furnace at the time of its installation showed a loss of 
3.62 per cent when melting a charge of 2 540 pounds of manganese bronze. In this 
furnace the flame is reverberatory and the charges are comparatively heavy. In the 
crucible furnaces, the metal being in the crucible, the flame does not come in direct 
contact with the same and the loss is comparatively small, being not more than 0.5 
per cent in the case of composition. 

Thelosses in melting yellow brass and manganese bronze in furnaces of the open- 
flame type will approximate 6 to 7 per cent. 

Reply 84, subdivision 32. —Crude oil is piped from tank about 25 feet from furnace, 
forced up to furnace by air pressure, and heated by steam before entering burner. 
Air comes from positive blower. Air pressure in No. I furnace, 12 ounces; in No. 2 
furnace, 15 ounces; down draft. Specific gravity of oil, 0.96 at 15° C. (California oil). 

We have no regular amount per day, as it depends on what work we have to pour. 
We melt from 300 to 1,500 pounds per day with our No. 2 furnace, and from 300 to 
1,000 pounds with our No. 1. 

The coke-fired pit furnaces are best for particular mixtures, as there is less chance 
for oxidation and consequently less loss in melting and in casting. We have excellent 
results with open-flame furnaces. If there is any difference in the metal, it does not 
show in the physical tests. All of our heats are tested and analyzed. 

Reply 85, subdivisions 5, 28, 33. —The advantage of the crucible type of oil furnace 
is that it is compact, easy to handle, and radiates little heat. The disadvantage is that 
the life of crucible is short. Our furnaces are used only intermittently. 

Reply 86, subdivisions 19, 31, 33. —In the spherical, open-flame furnaces it has been 
found best to keep the auxiliary cover closed, depending upon the pouring spout 
entirely for the escape of gases. A recent test of the oil used gave the following results: 
Gravity of oil freed from water, grit, etc., at 60° F., 17.3° B.; specific gravity 0.9505; 
percentage of water 0.42 per cent; percentage of grit, etc., 0.34 per cent; calorific value 
of 1 pound of pure oil with water vapor due to hydrogen content uncondensed, 17,605 
B. t. u.; same, water vapor condensed, 18,790 B. t. u. 

One man handles all three spherical open-flame furnaces, makes necessary repairs 
on linings daily, and cares for the ladles used in carrying the metal to the molds. 

No reliable data on oil consumption are at hand. Oil for entire foundry passes 
through one meter only. It is estimated that it takes 1 gallon of oil to melt 50 pounds 
of metal in the open-flame furnace. 

Linings in the open-flame furnaces have been known to last for two years, but 18 
months is more nearly the usual life of the lining, and constant attention is nessary to 
make them last for that length of time. Inspections are made daily and repairs made 
as found necessary. 

The open-flame furnaces are used successfully in the manufacture of all the general 
run of composition castings, but can not be depended upon for castings subjected to 
very high pressures. For castings requiring high tensile strength, or that must with¬ 
stand high pressures, the crucible seems the only reliable furnace. The open-flame 
furnaces of both types can be run more economically and efficiently than the pit or 
crucible furnaces. 


94 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


In the egg-ehaped opon-tlamc furnace the oil lined in name as described for the spher¬ 
ical furnace. The air in supplied from a high-pressure line; the pressure used at the 
furnace in not known, being regulated by the attendant. The pr«*ssure of oil at the 
burner in from 17 to 20 ponndn, the exact pressure not being known. 

The burners are of the air-atomizing type; twoare used, one at the center of each cud 
of the double chambers. The cluunbers being joined at the center, the jetn from the 
burners uingle and combuntion in made more complete thereby. 

The clans of melting done by these furnaces, reducing scrap to ingots, requires the 
services of two men, one to attend the furnace, the other to handle the miscellaneous 
ocrap. It is estimated that l gallon of oil will melt 50 pounds of metal in this type. 

These furnaces arc used almost exclusively for melting scrap metal, and are used 
intermittently. There are, therefore, no reliable data regarding relining. They are 
carefully watched and repairs made as found necessary. 

In the tiltingcmcible we estimate that 1 gallon melts 50 pouudsof composition metal; 
for babbitt, 100 pounds per gallon of oil is melted. We have no means of determining 
exact amount used. 

We get three heats of composition, or eight to ten of babbitt metal. For melting 
babbitt, the crucibles last so long that no data are at hand regarding the number of 
heatc they will stand. 

These furnaces are used almost exclusively for the manufacture of babbitt metal 
and are seldom used to the limit of their capacity. The maximum amount of babbitt 
that can be melted in one day of eight hours is 2,GOO pounds, using both furnaces, 
one melting 100 pounds each heat, the other 160 pounds, ten heats being taken off. 
This metal is made from the original Babbitt formula: 88.8 tin, 7.5 antimony, and 
3.7 copper. 

The fuel used in the tilting-erucible furnaces is not definitely known. It is esti¬ 
mated that 1 gallon of oil will melt 50 pounds of metal. One heat only is taken off 
in a day from these furnaces. Thee© furnaces are used only for melting manganese 
bronze, gun and valve metal when required in quantities exceeding 1,200 pounds, 
their principal service being in the casting of propellers, propeller hubs, and sleeves 
for propeller shafts. Their use is therefore infrequent and the lining lasts indefinitely. 

The largo crucibles are used so infrequently that no definite data are available by 
which to determine the number of heats that may be taken from them. 

The capacity of the small furnaces is 750 pounds each, using crucible No. 275; the 
large furnaces use crucibles No. 600 having a capacity of 1,800 pounds each. Manga¬ 
nese bronze, gun ami valve metals are the only ones melted in these furnaces. 

The principal losses are due, in the melting of manganese bronze, to escape of zinc 
and losses due to slopping of metal when being handled by the crane. In handling 
gun metal the loss is due to slopping of metal. The amount recovered is very small, 
and as it is recovered as part of the general miscellaneous waste in the shop, no definite 
data are obtainable. It is estimated that the loss due to melting manganese bronze is 
about 6 percent. In the melting of gun metal, the estimated loss is 4 percent. 

We have two square and two round, pit, oil furnaces. Square ones 19 by 19 by 27 
inches ; round ones 16 inches in diameter by 27 inches deep. Round furnaces made 
so by filling up comers of square ones. Nos. 30 and 100 crucibles used. The quantity 
of fuel used in these is not definitely known. Supposition is that 1 gallon of oil melts 
50 pounds of metal. The heats are irregular in quantity and kind of metal used and 
no reliable data can be given. No data on losses can be given. The losses when 
metal is melted in pit crucibles are very small; supposed to be less than 2 per cent. 
No yellow metal is made from the pit furnaces. Used for phosphor bronze, gun and 
valve metal. No average can be given. 

Reply 87, subdivisions £, 4. —Nos. 45, 70, and 100 crucibles are also used in the smaller 
furnaces, and run from 25 to 30 heats on red brass. 




DETAILED RESULTS OF INVESTIGATION. 


95 


The stack is 70 feet tall for 22 furnaces. The gross loss on red brass is estimated at 
2 per cent, on manganese bronze one-third to one-half ingot, two-thirds to one-half 
gates, 7 to 10 per cent. We average 45 pounds of coke per hundredweight of metal 
on* red brass; 50 pounds on manganese bronze. “Pinch” tongs are used. Square 
furnaces are used because of the ease of firing and of repairs, also because they give 
room to get the tongs down in the furnace. A heat can be gotten out more quickly 
with small coke than with large. 

Reply 88, subdivision 19 .—Have had experience only with pit furnace using coke 
and with oil furnaces. Find oil is cheaper than coke and gives better results all 
around. Data given are those obtained by writer when trying out an oil furnace with 
view of replacing pit coke furnaces with oil furnaces. 

After a few hours instruction on previous day from representative of furnace makers, 
I lit the furnace at 7.35 a. m.; put metal in at 7.44; took first pot out 9.32, second at 
10.44, third at 11.53; furnace stood idle until 1.05 p. m.; took fourth pot out 2.30, fifth 
at 4.05, and sixth at 5.05. Nine hundred pounds was melted, all being new mixture 
of red metal; 18.8 gallons of oil w*as used. 

On the following day the furnace was lit at 6.56 a. m., the first pot was removed at 
9.11, second 10.28, third 11.53, fourth 1.02, fifth 2.09, sixth, 3.14, seventh 4.17, eighth 
5.10. Seventy per cent new mixture, 30 per cent gates; 1,480 pounds melted. I 
mn the furnace personally for nine days until the crucible gave out, melting 9,085 
pounds in 58 heats, using 2.13 gallons oil per hundredweight melted. Furnace lit 
81.44 hours. In the above run the pouring pot was heated in pit furnaces. Following 
above we put in pot heater and oil burner on core oven. In the operation of the furnace 
for nine days I discovered a number of things which I thought would add to the life of 
the crucible, and which proved out in a later run of three months during which time 
I had a melter in charge of furnaces, but gave them careful watching personally, with 
results as follows: In March, April, and May 192,580 pounds metal was melted, 
6,511 gallons oil was used, or 3.38 gallons per hundredweight melted. This includes 
all oil used for baking cores, pot heater, waste, etc. The average number of heats 
per No. 60 crucible during this time was 71J; highest, 82 heats; lowest, 52 heats. 

After the melting had been left to the melter, ouraverage number of heats per crucible 
dropped to 61 for the following three months. The oil used was crude oil as pumped 
through a Pennsylvania pipe line. In 1909 we were troubled with so much sediment 
and water in oil that we changed to light-colored fuel oil, which we purchased in tank 
cars. Before making this change in oil our crucibles w r ould not last as long as was 
customary, and I tried a number of makes, but have been unable to get as good results, 
and have been unable to locate the trouble outside of the crucible itself. We are now 
getting only 35 to 51 heats on No. 60; 25 to 35 on No. 125. We did have one recently 
that went 41. 

Reply 89, subdivision 7—We run very light castings; hence require hot metal, and 
the metal is often held in the furnace for some time after it is ready to pour, waiting for 
molds; hence the high fuel and loss figures. 

We have a foreman who used to use a cupola for large melts, with hard coal as fuel, 
but he can give no figures on fuel consumption or metal losses. 

Reply 90, subdivision 14— A “feeder” is used, and the air is preheated by passing 
around the furnace shell through an outer casing. The crucible is a tall conical form of 
English crucible. The 450-pound size lasts 45 heats, and the 150-pound size, in a proper 
sized furnace, lasts 55 to 60 heats. The fuel consumption in the 450-*pound size is 
15 pounds of coke per hundredweight of metal; in the 150-pound size, 20 pounds. We 
reline the bottom part of the furnace every 1,000 heats. .The upper part lasts longer. 
A comparative test of a crucible, tilting, oil furnace against this type showed a melting 
loss of 5.03 percent in the oil and 4.90 per cent in the forced-draft, tilting, coke fur¬ 
nace. The oil consumption is 2.8 gallons per hundredweight. 

Our loss in running down chips to ingot on 100,000 pounds was 6 per cent. 


90 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


Hr ply 91, subdivision 32 .—We have displaced our pit coke furnaces by the open- 
flame with entire success. Our castings have to stand high pressure. We have tried 
the forced-draft, tilting, coke furnace, which can not coin pare in economy with the open- 
flame. We also tried out a rectangular-pit, oil furnace with one burner, a dozen 
crucibles being set into the pit. The heats tc*ok so long that the loss was gn*at, the 
oxidizing flame scored the crucibles badly, and their life was short, and the furnace 
was hard on the.tendera. We have abandoned this type of furnace. We use charcoal 
and salt, skimming off the slag and putting it back with the next heat. Our j>ouririg 
crucibles are preheated in a pit, coke fire; it takes 250 pounds of coke to heat flouring 
crucibles to handle the pouring of 6 tons of metal. 

Reply 9i, subdivision 32. —We are also melting brass in crucibles by natural draft, 
. using coal for fuel. The life of these crucibles is about 1G to 18 heats. 

(Note that small heats—only one-fourth the rated capacity of the furnace- are 
made, with good fuel efficiency. No figures were given on metal biases.] 

Reply 93, subdinsion IS. —It has never been necessary to reline any of the fur¬ 
naces that we have ever installed. Occasionally we go over the brick linings with a 
solution made of carborundum fire sand. This seems to work very satisfactorily in 
preserving the brick. We have a number of these furnaces that have been in constant 
use for five or six years. 

The fuel-oil furnace has proven much more satisfactory than the ordinary coke fur¬ 
nace and the stoker type of furnace using coal as fuel. One of the good features of a fuel- 
. oil furnace is the low shrinkage. It requires much less labor to operate this type of 
furnace. A crucible will last much longer. We do not believe there is any material 
difference between the metal melted in a coke and that melted in a coal furnace. We 
have never made any tests in this respect but we feel that conditions favor the fuel oil 
owing to the fact that the heat is much more uniform. 

The consumption of oil per hundredweight of metal melted when No. 50 and No. 
GO crucibles are used is practically the same as when the No. 80 crucibles are used. 

When the No. 50 and the No. GO crucibles are used in the oil furnaces that we are 
now using, the volume of flame around the entire crucible is much larger than when 
a No. 80 crucible is used. This results in getting more heats i>er day with the smaller 
crucible with practically the same total w’eight of metal melted. 

With reference to the stoker type of furnace, using coal for fuel, they did not work 
out very satisfactorily. Our main trouble was to get a brick lining that would with¬ 
stand the heat produced by this furnace; as the cost of upkeep was very high we threw’ 
out this entire equipment. 

We regret that we are unable to give you any information with reference to the fuel 
consumption per hundredweight of metal melted as well as the loss in shrinkage as we 
destroyed all of these records. 

The type of stoker furnace we tried was so arranged that a number of crucibles could 
be set on the fire at the same time. There were openings in the floor through which 
the crucibles were put into the furnace. These openings resemble the ordinary fur¬ 
nace pits of the regular type of coke furnace commonly used by a great many foundries. 
We are of the opinion that this type of furnace is not used to any great extent; in fact, 
the w’riter is of the opinion that the manufacturer has discontinued making them. 

[The manufacturer wrote as follows: “The stoker type of furnace which we installed 

at-was a failure. We have not done anything w'ith it for the past four or five 

years.”] 

Reply 94, subdivisions 5, 25, 18, 33. —The open-flame furnace gives more of a low in 
melting, the flame coming-in contact with the metal. The crucible furnaces give 
better results, on account of flame not coming in contact with metal, making the 
oxidation less, and making the mixture of metal more unifonn. The ojen-flame 
furnace is not in use much; only for red-metal mixtures. To get same mixture on 





DETAILED RESULTS OF INVESTIGATION. 97 

yellow casting we must charge 10 to 15 per cent more zinc to overcome the excessive 
loss. The loss in this furnace on red brass is 2.1 per cent. 

We have run the gas furnaces only a few days. 

Reply 95, subdivision 10. —[See notes on Reply 17 as to furnace tenders in rolling 
mills.] We have experimented a little on a 5-ton reverberatory furnace [probably 
fired with producer gas] but have not yet gotten it to the point where it is satisfactory. 
About 1 per cent of the melt is recovered from the ashes. The reasons why rolling 
mills so generally use the square furnaces instead of the round are shown in our expe¬ 
rience which has been as follows: 

It is necessary for us to have a certain space between crucible and furnace walls 
in order to put tongs on the crucibles. With the square furnace we utilize space on 
corners for this. We can therefore use a square furnace having less horizontal area 
than that of a round furnace that would give us room to adjust tongs. Tho quantity 
of coal contained in the square furnace is enough to melt the charge; consequently 
the extra coal in the round furnace would be burned without helping much to melt 
the brass. This is in line with our experience that the coal consumption is less in 
square fires. Also, as the heats we use are high, and our furnaces must be relined 
frequently, it is desirable to have a simple form of lining and to use standard-shape 
fire bricks, which are cheaper. 

Sand-casting shops pour their metal at a lower heat than we do and also have less 
bulky scraps to melt. It requires considerable coal for us to raise the heat of our brass 
above the heat at which sand-casting shops pour. 

Regarding melting in larger quantities, the objection has been the difficulty of han¬ 
dling large quantities. We are not able to pour into ladles and thence into molds on 
account of having to pour at high heat. 

Reply 96, subdivision 82. —This is a double-chamber furnace. Lining is of an 
asbestos, high-temperature cement, about 6 inches thick. 

Using this cement, furnaces require relining about every six months, according to 
grade of metal melted. There are cases where it runs more or less. Repairs are made, 
such as daubing around charging hole, on an average of three times a week, or as often 
as required to keep furnace in good shape. 

Reply 97, subdivisions 1, 24, 30. —No. 60 and No. 80 crucibles are used. Forty-eight- 
hour coke is used for pit furnaces—gas and oil for tilting furnaces. Natural gas, 
under a 6-ounce pressure; air, under an 18-ounce pressure. Three furnaces per tender. 
Fuel consumption, 139 cubic feet of natural gas, 2.8 gallons of oil, or 255 pounds of 
coke per 200 pounds of metal. Four heats per day. Working day, 12£ hours. Patched 
once per month. Crucible life, 23 to 28 heats. 

Charge per furnace per day, 900 pounds: New metal 294 pounds, turnings 160 
pounds, gates, sprues, and scraps 446 pounds. Gross loss, 3 per cent. Loss in foun¬ 
dry from all causes, 2.8 per cent. Yellow brass and red metal melted. 

We don’t find much difference in furnaces; both satisfactory'. 

[A request for more detailed information to allow tabulation of data for the different 
furnaces was unanswered.] 

Reply 98, subdivision 28. —The net loss is uncertain; we estimate it at $ per cent. 
Fuel oil is superior to coal; the general appearance of castings is better and other con¬ 
ditions are more satisfactory. 

We also use egg-shaped, open-flame furnaces, in which we estimate an oil consump¬ 
tion of If gallons per hundredweight of melt. No data on losses. 

Reply 99, subdivisions 12, 38 .—We find we get less loss from porousness on hydraulic 
tests, and metals pour better from pit furnaces. 

Reply 100, subdivisions 20, 31 .—-Our net loss is 3$ per cent. This percentage may 
seem pretty high, but we have no mechanical means for recovering brass from the 
slag, dross, etc., but recover some of this by getting a good price for the refuse when 


44712°—Bull. 73—16-7 



98 


BRASS’?URNACE PRACTICE IN THE UNITED STATES. 


wo sell it, and no account has been taken of that. The number of heats from a No. 
125 furnace and also the No, 45 furnace depends upon the kind of metal used. A 
heat can bo run down quicker if all ingot is used than when scrap, such as screw- 
machine turnings, clippings, etc., is used. On our work, which is almost all tho 
latter material, the larger furnaces require more labor than the small ones. We do 
not keep the time separately, but we have tliree men to take care of 12 furnaces 
and one man looks after the two large ones and di*>s some work on tho small ones. 
The average weight of a heat in the tilting furnace is about 350 pounds, in the small 
ones about 130 pounds. 

The life of a crucible in a tilting furnace, other things being equal, is longer than 
that of crucibles in the pit furnace when tho crucibles are removed with tongs. 

In regard to the amount of oil used in each furnace, we have no way of knowing, 
as the oil is all taken from one main lead pipe, and we have never measured individual 
furnaces. 

Reply 101 , subdivisions 1, IS. —There is no difference between the metal from tho 
pit and that from the tilting, coke furnaces. In the tilting furnaces we lose 6 to 
10 per cent on yellow-brass turnings. 

Reply 102 , subdivisions 16, 28. —Our furnaces are designed to use either gas, oil, or 
coke. Oil is used at the present time. We have stopped using the tilting furnaces, 
the pit furnaces doing away with the oxidation due to the double jxjuring when metal 
is transferred to a ladle. 

We are using low-pressure air and high-pressure oil in the oil burner, which is much 
better than the burners using high-pressure air. 

Reply 103 , subdivision 16. —The furnace is cylindrical; top 2G inches, bottom 32 
inches in diameter; inside depth, 1GJ inches; outside depth, 2 feet 5 inches; depth of 
cover, 4$ inches, lined with fire brick approximately 5 inches thick. 

Reply 104, subdivisions S3, 35. —The figures on speed of melting in the natural-gas, 
open-flame furnace are from special tests. The normal speed is less than the normal 
speed when the furnaces are oil fired. If we drive the furnaces we can double the 
normal speed [given in the table] on the oil-fired furnaces. 

The melting loss with natural-gas firing is about 10 per cent greater than with oil, so 
we have gone over to oil, although we formerly used natural gas very largely. Tho 
better results with oil firing are due to greater speed in melting. 

The borings are put in the bottom of the furnace, gates on top of these, and the 
ingot on top of the gates. We have tried briquetting the borings under very heavy 
pressure, forming them into rather solid blocks, but the melting loss of tho whole 
charge, put in as above stated, was decreased less than 0.1 per cent figured on the 
total charge, which did not pay for the briquetting. On charges of all borings results 
might be better, but no such tests were made. 

In order to get a low melting loss the open-flame furnaces must have the lining kept 
smooth. On the top and sides of the furnace we use a fire brick much used in blast 
furnaces, and a cementing material of German fire clay, 1 part, and ground ganister, 
3 parts. This is swept into place by a revolving templet. 

It is best not to rock the furnaces during the melt, as this increases tho oxidation. 
We reduce the size of the pouring spout so as to keep as high a pressure in the furnace 
as possible. The metal melted in the open-flame furnaces is equal in quality to that 
melted in other types. 

Reply 106 , subdii'ision 17. —We have tried building these furnaces in a vertical, 
cylindrical shape, but could note no advantages over the square ones; as they were 
harder to construct, we ceased to build them that way. For combustion wo use blower 
air at low pressure. 

In regard to fuel-oil consumption on the basis of gallons per hundredweight of metal 
melted, we have run a couple of tests on this basis. Although at the time the tests 
were run we were not getting the highest efficiency from our fuel oil, we found that 






DETAILED RESULTS OF INVESTIGATION. 99 

it took about 8 gallons of oil to melt 100 pounds of metal. Our experience shows that 
the net percentage lost in melting is less than 1 per cent. 

Reply 107, subdivision 7 .—[Subdivision 7 shows “average analysis of product” in¬ 
stead of analysis of a single alloy. Reply states: “Average net loss on yellow-brass 
scrap 6 to 10 per cent.”] 

Reply 108, subdivision 25 .—The furnace is of the recuperative type and is built in 
two sizes to accommodate a No. 50 or a No. 100 standard crucible. The recuperative 
and pit settings are placed in a sheet-iron shell, the bottom sheet being reinforced by 
two I beams. The crucible pit is formed by an inner ring of circle fire brick, 4h inches 
thick, and an outer ring of brick 2£ inches thick. Between the two is an annular space 
about 2 inches wide, filled with asbestos-fiber insulation. The furnace is provided with 
three air-blast burners, to which the air and gas are brought through separate pipe rings. 
Each burner is made with an inner and outer tube, the mixture of air and gas taking 
place at the tip of the burner. The tliree burners are placed 120 degrees apart and are 
inserted into special burner tile provided at the bottom of the inner fire-brick ring. 
The axes of the burner are tangential to a circle whose diameter is slightly smaller 
than the diameter of the crucible pit, thus insuring a perfectly reverberatory action 
of the three flames. The flames enter the pit below the bottom line of the crucible, 
so that there is no direct action of the flames upon any part of the crucible. In this 
manner all burning of holes into any part of the crucible or any uneven heating is 
avoided, lengthening materially the crucible’s life. The inside surface of the pit is 
lined with high-temperature cement lining 1£ inches thick. The crucible is placed 
on a removable, circular bottom block. A cupola-type drop bottom, which can be 
released from the operating floor, permits prompt dumping of the furnace in case of 
failure of a crucible. 

A waste-gas flue connects the crucible pit with the recuperation chamber, which 
consists essentially of a suitable brick setting and five cast-iron recuperator sections. 
The sections are j>rovided with ribs to increase the radiation surface and have three 
compartments to prolong the time of contact of the air with the radiator surface heated 
by the waste gases. The cold air from the blower enters the last section in the furnace 
and passes through each successive section and out of the first into the air ring that 
supplies the burners. A displacement of 288 cubic inches of air per revolution, when 
operating on an air pressure of 2 to 3 pounds, is customarily used. The power required 
to run it is about 1£ horsepower. 

Better control of heat in the gas furnace means cleaner castings and less loss; small 
oxidation seems to go with sound castings, a result especially noted in thin or difficult 
work. 

Several analyses were made of the waste gases by means of an Orsat apparatus. The 
results of these analyses indicated the presence of a slight trace of carbon monoxide, 
never, however, exceeding j0.4 per cent, besides, of course, the proper proportions of 
nitrogen, water vapor, and carbon dioxide, results that show absolute control of gas 
and air regulation, bringing about perfect combustion, and hence fuel economy. 
An examination of the hot crucible after the test showed that the highest temperature 
existed at the bottom, insuring melting of metals from the bottom up, an essential 
requisite with the foundryman. The temperature of the waste gases at the exhaust flues 
was about 200° F., indicating the efficiency of the recuperation. Loss of heat from 
radiation was negligible, as the temperature of the outside of the shell was little above 
the room temperature. 

It is almost impossible to operate an oil furnace with a reducing flame, on account 
of the excessive amount of air that must be forced into tho furnace to increase the 
rapidity of melting. To obtain a reducing flame, it is necessary to have the right 
proportions of air and oil, as the oil should be sufficient to burn up the amount of 
oxygen that is forced into the furnace. This is almost impossible as the oil and air 
pressure are continually varying and the valves can not be regulated to get the right 


100 


1)HASS-FURNACE PRACTICE IN T1IK UNITED STATES. 


proportions. Therefore too much or too little oil and air are allowed to enter the 
furnace. This condition necessarily results in imperfect combustion, hence fuel 
waste. The wasto-gus analyses in the above teat show that practically perfect com¬ 
bustion of gus existed throughout, after the mixture of gas and air had once been 
regulated. The importance of this factor in melting can not be ovonutimated. 

Aside from the effect upon castings, perfect or imperfect fuel combustion has a 
decided bearing upon prolonging or shortening the life of a crucible. The most serious 
effect in the use of oil is at the start with new crucibles. With an excess of oil entering 
the furnace, there being too little air to form perfect combustion, the surplus moist 
oil gases will he forced against the crucible walls, producing w*hat are known us “alli¬ 
gator’’ cracks, and layers will peel from the crucible to a depth depending upon how 
far the moisture from these hot oil gases has penetrated. On the other hand excessive 
air produces an oxidizing condition, which extracts the carbon from the crucible wall, 
leaving a porous-clay structure. Although the wall may retain its original thickness, 
the graphite has been taken away, and the crucible is ready to crack, its vital sub¬ 
stance having disappeared. Again, owing to the arrangement of the burners, de¬ 
scribed above, the gyrating motion of tho flames in this gas furnace is more perfect; 
hence the heat distribution is more even than in the case of the oil furnace, whero a 
single burner is used to obtain these effects. Tho result is a uniform heating of the 
crucible walls, allowing them to expand equally as the temperature rises. In this 
manner all local strains in the crucible walls due to uneven heating are avoided. 
Another cause tending to shorten the life of crucibles, and one freely admitted by oper¬ 
ators of the old-style coke furnaces, is the difficulty experienced by the furnace tender 
in taking hold of the hot crucible with the tongs, preparatory to lifting it from the fur¬ 
nace for pouring. Frequently tho rocking and jarring of the crucible with tho tongs, 
necessary to penetrate tho closely packed incandescent coke in order to get a firm hold 
of the crucible, results in prematurely cracking the crucible, or in what are known 
as pinhole leaks. That this difficulty is obviated in the use of a gas furnace is self- 
apparent. 

[This reply and the data were furnished by the gas company supplying the gas to 
the foundry, not by the foundry itself.] 

Reply 109, subdivision 8. —Wo use 100 pounds of hard coal and 2 hods of charcoal 
to melt 150 pounds of metal. 

Reply 110, subdivision 7. —Round furnaces give more uniform heat [than square ones] 
and are best for all purposes. 

Reply 118, subdivision 1 . —In my 32 years’ experience in brass foundries I find a 
vast difference in brass-melting furnaces. I find that the old pit coke furnace, with 
the new grates and double-bottom plates, are the best in the long run; properly han¬ 
dled, they produce the best results, and the least shrinkage of any furnace of other 
makes and fuels; when you put your metals and mixtures into the crucible, you can 
depend on getting the results, barring two things, overheating or a leaky crucible. 

Pit furnaces w ith crucible, and oil or gas fuel, come next in my estimation and ex¬ 
perience. A furnace in which the oil or gas bums directly over or in and about the 
metal is the poorest furnace, as there is too much shrinkage and loss of metal—the lead, 
zinc, and tin bums too easily and too fast, and consequently tho mixture has changed 
in melting, and the quality is not the same as we get from pit furnaces. I have never 
tried to find out the difference by physical tests—only in machining and colors, and 
there is a vast difference there. 

Reply 114, subdivision 1 .—Oil furnaces are fit only for common heavy work, such as car 
bearings, ingots, etc. Coal or coke furnaces are the best for cheapness and fine results. 

Reply 115, subdivision 11. —We do not know how many furnaces one tender could 
handle, as we operate only three.* 

It Is reported to the office that the life of a crucible is about 45 heats, but we do not 
guarantee this assertion. It is only a short time since our foundry was a one-man 


DETAILED RESULTS OF INVESTIGATION. 


101 


foundry. There has really been no system upon which it has been run, and it is only 
^ithin the last month or so that wo have been in a position where we could even think 
about getting a definite line on its workings. 

Reply 117, subdivision 31. —The furnace is of an elliptical shape. The dimensions 
are: Height 4 feet, width 3 feet, length 4 feet 9 inches. The opening for the crucible 
is round. 

We find the oil furnace a decided improvement over the hard-coal or coke furnace. 
There are no skimmings to become mixed with the coal or coke. When a crucible 
breaks in a coke or coal fed furnace there is a decided loss. When it breaks in a 
tilting, oil furnace the loss is nominal, as the molten metal may be poured out im¬ 
mediately. 

The tilting, oil-burning furnace saves the labor of one furnace tender and eliminates 
much heat, dirt, and floor space. In addition, the fuel is nearly one-half cheaper. 
It is also much easier to charge a tilting furnace. 

W e obtain a much more even heat and a stronger and more even metal by mixing 
it all at one time in place of mixing it in several smaller pots. 

In watching one furnace a tender may give greater care than to several, eliminating 
chances of burning the metal. 

Reply 118 , subdivision 10. —We estimate 154 pounds coal for 2 heats from a No. 30 
crucible. We used 32 tons of coal to produce 32,202 pounds of yellow-brass castings 
(exclusive of gates and sprues). 

Reply 119, subdivision 1 . —Our furnace pit is made of concrete and is 44 feet long, 
9 feet wide, and 7 feet deep, with 12 ordinary coke furnaces with drop grates of our 
own design and make. 

All the furnaces are circular and all of the 6ame depth; three sizes of diameter to 
take No. 40, 60, and 80 crucibles. We allow about 4 inches on the sides for the coke. 
The lining is fire brick, about 4 inches thick. 

We use 72-hour Connellsville coke, egg size. Natural draft is furnished by around 
brick chimney about 60 feet high, 3 feet at the base and 2 feet at the top. The smoke 
tunnel leading to the chimney from the furnaces is 2 feet wide and 3 feet deep. 

We believe three furnaces are all a furnace tender can attend properly. We have 
no data on the consumption of coke. 

We believe that a natural-draft coke furnace is the better furnace for getting but 
specific alloys in smaller quantities, and with an experienced furnace tender the loss 
in melting can be held lower because the heat is better regulated. On the other hand, 
if heavy castings are to be made, like railroad journal boxes and bearing boxes of any 
kind, which require big weight in metals, we believe an oil furnace is the best, because 
of the larger quantity of metal which can be melted. Our experience, however, is 
that a forced-draft oil furnace is too expensive and too wasteful to be of any use for 
melting yellow brass, as the loss of zinc is too great. An oil furnace also has its place 
in a city where floor space is high; but in a smaller town where floor space is cheap we 
believe that the natural-draft coke furnace is the best. 

Reply 120, subdivision 24. —We used in 1912, 56 No. 40, 117 No. 50, and 18 No. 60 
crucibles. Heats per crucible averaged 10.8. 

Advantages of gas are ease in starting, absence of dust and ashes. Can notice no 
difference in the quality of metal. 

Reply 121, subdivisions 1, 28. —We are using both coal-fired pit furnaces and oil-fired 
tilting-crucible furnaces. We have six pit furnaces at present, but we contemplate 
doing away with part or all of these in the near future and substituting either oil-fired 
or coke-fired furnaces. We are also considering an electric-heated furnace of new 
design. 

We used to use an ordinary fire-brick lining, but are now using, with considerable 
success, aliningconsistingof firebrick, faced with a mixture of carborundum and kaolin, 


102 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


with water-glass binder to a depth of about 1$ to 2 inches; double thickness of wall, 6 to 
t>$ inches. Wo use nl>out 85 |>er cent of carborundum in the mix. 

Wo use No. 125 |M>ts in the tilting furnaces uud No. 40, 60, and 80 pots in the pit 
furnaces. 

One furnace tender and a helper handle all the furnaces that are ojm* rated daily. 
Generally thro© of the tilting furnaces are going at ono time and at least two of the pit 
furnaces. 

To date we have never made enough tests on fuel consumption to warrant giving 
figures. Recently we made gome tests on one of the tilting furnaces that accrued to 
indicate that we were using more oil than the claims of the manufacturers demanded. 
It would be perhaps advisable to test the consumption on more than one furnace before 
any figures are given. 

The working day is 10 hours. Occasionally one or more furnaces aro started an 
hour earlier in the morning, if production demands such procedure at the time. 

The pit furnaces are relined on the average once in six months. The oil furnaces are 
refaced about once in three months. 

In the pit furnace the life of the crucible ranges between 20 and 30 heats; in the oil 
furnace, between 10 and 18 heats. 

Our alloy list contains about 20 different mixtures, of which about one-half dozen 
are cast in rather large quantity. 

We cast four alloys in which the copper runs above 80 per cent, which includes our 
scrap alloy above referred to and several types of gun metal. We also cast aluminum 
and one or more of its alloys, as well as bearing metals. 

The only furnaces we have tried are those that are now in operation. We have 
never tested bars poured from both types to determine the comparison between the 
metal taken from each. 

Reply 122, subdivision 9. —[This reply was noted on the question sheets, without 
address.] 

Reply 123, subdivision 3. —Coke furnaces are best for high-zinc alloys. 

Reply 124, subdivision 20. —We find that the crucibles do not average so great a 
number of heats in the oil furnaces as in the coke furnaces. 

Reply 126 , subdivision 1 . —Stack 65 feet high. 

1 have had the most uniform brass, with the least percentage of loss, both in metal 
and in castings, when using good coke not too high in sulphur. Oil fuel oxidizes the 
metal more than coke, which makes better pressure-tight castings. Never made 
physical-tost comparison. Get a more uniform temperature with coke, owing to 
operator’s inability to judge the metal accurately in an oil furnace. 

Reply 128, subdivision 7. —We find coal the best. 

Reply 132, subdivision 7. —There may be other good furnaces, but 'when you aro 
required to produce a bronze to analyze similar to the Government requirements, 
with a tensile strength of 30,000, an elastic limit of 15,000, and an elongation of 15 
per cent in 2 inches, you can not better the results obtained from the crucible or pit 
furnace. 

Reply 134 , subdiinsion 16. —A home-made burner is used, consisting of an oil nozzle 
with a $-inch outside diameter and a ^y-iuch hole in the end, which is brought down in 
conical form. Around this nozzle tube and concentric with it is a tube of f-inch 
inside diameter, which carries compressed air to aid in atomization of the oil. Around 
these tubes and concentric with them is a 1^-inch tube carrying a low-pressure fan 
blast, furnishing air for combustion. 

We use scrap car brass with one-cighth new copper. We use the slag again on the 
Dext heat. We charge first the light brass, then the now copper, with a special flux 
[the active agent of which is probably manganese dioxide], then the old slag and sprues, 
and then scrap journal bearings. Our gross loss is 6 per cent, which is very small, as 
we use crushed charcoal on the top of the charge. We make two 1-hourheatsaday, 


DETAILED RESULTS OF INVESTIGATION. 


103 


using 80 pounds of metal per heat; 2 gallons of oil used per day per burner. [This 
would amount to less than 1.3 gallons per hundredweight, a figure that is doubtful.] 

Reply 135, subdivision 3 .—We use 25 pounds of coke per hundredweight when the 
furnaces are new; when the lining is worn thin, about 33. A good deal depends on 
the weather. 

Reply 136, subdivision ID .—The oil is preheated before entering the burner. 

Reply 137, subdivision 3 .—Tried city gas at $1 per 1,000 feet, which was too 
expensive. 

Reply 139, subdivision 7 .—Stack 60 feet high, 18 inches in diameter. 

Reply 140, subdivision 10 .—[See notes on Reply 17 as to furnace tenders in rolling 
mills.] 

We have 25 fires on each stack. Stacks are 100 feet high and 3£ feet in diameter. 
The length of heat on a No. 70, No. 80, or No. 90 crucible, coaled up to the top, and 
each in the same sized furnace, is the same; that is, the fuel consumption in the larger 
crucible is less per hundredweight of metal melted. We are going to try round fur¬ 
naces the next time we line any up. 

Tests on losses on yellow brass with all new metal gave 2.5, 3.1, and 1.8 per cent. 
On a test to see the effect of holding the crucible in the fire too long we got 2 per 
cent loss when the crucible was in the fire 7 minutes after speltering, and 4.7 per 
cent loss when it was held 22 minutes after speltering. 

We sometimes use a little coke if the pot “hangs” [does not melt down with normal 
rapidity]. 

We have tried open-flame oil furnaces for melting yellow brass, but had too much 
zinc loss, and the metal poured from them could not be rolled cold, although it could 
be rolled hot. We calculate that 1 to £ per cent of the total melt is recovered from 
the ashes. 

[The crucible is set in a pouring shank, which is mounted on trunnions, and is 
tilted by a handwheel and gearing, the whole being mounted on a truck that is pushed 
on a track laid beside the pit in which the ingot molds are set. The truck and crucible 
are then pushed along till the lip of the crucible is over the gate of the mold, when 
the metal is poured by means of the liandwheel, the diameter of which is at right 
angles to the course of the track. Pouring is as steady and as rapid as in ordinary 
practice with a rope hoist. The man pouring is out of the zinc fume, as is his helper, 
who skims the metal with a long skimmer. lie is also protected from the heat by a 
shield placed between himself and the pot, but not cutting off his view of the lip 
and gate.] 

Reply 141 , subdivision 10 .—[See notes on Reply 17 as to rolling-mill furnace tenders.] 

We tried an open-flame, oil furnace on yellow brass. No trouble was found in 
pouring into a ladle and from that into the molds, but the zinc loss W'as too high. 

Reply 142, subdivision 1 .—On yellow brass (76 per cent copper, 20 per cent zinc, 
1 per cent tin, 3 per cent lead) our loss averages 4 per cent. 

Reply 143, subdivision 7 .—We use three scuttles of coal to melt 150 pounds. 

Reply 144, subdivision 28 .—The average life of a crucible is 18 heats, with a maximum 
of 38 and a minimum of 4. 

The recovery of metal is considerable from slag, skimmings, etc., as we are using 
a cinder crusher, recently installed. The gross percentage of loss during melting 
averages 6£ per cent. The net percentage of loss remains to be determined when we 
have had the cinder crusher longer in use, and have secured some records from its 
operation. It is now operating on an accumulation of several months. 

Previous to the installation of these oil-fired, tilting-crucible furnaces, we used pit 
fires, but discarded them on account of the long time required before obtaining the 
first heat of the day and the expense of handling the coal and ashes. 

Reply 145, subdivision 27 .—[Reply to question “Give cubic feet of gas used per 
furnace per day ” was “100,000 cubic feet.” 


104 


RRASS-FURNACE PRACTICE IN THE UNITED STATES. 


Kopiy to question “Give total pounds of motel cliarged por furnace por day ” vm 
“687 pounds.'* These answers indicate tliat about 14,500 cubic foot of pas per hun¬ 
dredweight of inetal was used—a manifest error. A letter of inquiry on this point 
brought no reply.] 

Reply 146, subdivision IS. —The amount of fuel used by brass manufacturers averages 
about 2J gallons to 180 pounds of metal. [This is equivalent to about 1.4 gallons 
por hundredweight. No definite statement was made tliat tho oil consumption 
at this particular plant is as low as that.] 

We liave found the oil furnaces tho cheapest; with crude oil at 4 cents per gallon, 
delivered, we have an advantage of 30 to 33 per cent over coke. 

Reply 149, subdivision 9. —Our total output is 2 tons por week; we use 2 tons of 
hard coal per week. [It is not certain whether tho output refers to metal melted 
or to castings produced minus gates and sprues.] 

Figures are based on both yellow and red brass. 

Reply 150 , subdivision 17. —We prefer crucible furnaces for small operations. 

Reply 151, subdivision 10. —[See notes on Iteply 17 relative to rolling-mill furnace 
tenders.] 

We use a salt flux and skim into water, the charcoal and dross recovered being put 
back on other crucibles later, until the slag is too thick. Wo recover twice os much 
metal from the ski mini mgs as from the ashes. 

Reply 152, subdivisions 13, 30. —The difference between the weight of metal cliarged 
and [trimmed] castings delivered is 2.79 per cent. The net loss for 1912, crediting 
recovery from slag, grindings, spillings, and skimmings, was 1.86 percent. This 
figure covers all foundry losses, grinding losses, etc., as well as the actual melting 
loss. The actual melting loss, or difference between metal cliarged and poured, 
is 0.51 per cent. [This figure seems to be based on complete foundry records.] 

We have used ordinary pit furnaces and two makes of tilting coke furnaces and 
tilting oil furnaces. Each form of tilting, coke or oil furnace has been supplied with 
forced draft. Relative economy depends upon market values of fuel. Have noted no 
material difference in loss of metal during melting between oil and coke furnaces 
now in use with bronze mixtures, nor doesthere seem to be a difference in final analysis 
of the metal or of the castings in the testing machine. 

The air supply for both coke and oil furnaces is pieheated. 

The oil consumption runs from over 2$ gallons per hundredweight on the first heat, 
which takes a little over three hours, to 1$ gallons per hundredweight on the last, 
which takes a little less than two hours. 

Reply 154 , subdivision 14. —It lias been our experience that tne pit furnace is an 
ideal furnace, but we have noticed considerable economy in using the forced-draft, 
tilting, coke furnace, such as we are using, as it gets heats out much more quickly 
and gives better metal than does the pit furnace. 

[The reply to the question as to pounds metal per furnace per day was “2,000 
pounds;” as to pounds of fuel per furnace per day the reply was “150 pounds of hard 
coke,” or 7.5 pounds per hundredweight. A letter asking for verification of this 
low figure was unanswered.] 

Reply 155, subdivision 7. —After the first three months the furnaces are repaired 
about once a month. They are relined every six to eight months. 

Reply 156, subdivision 32. —We have no positive figures for amount of fuel used a day 
under present operating conditions, but previous tests show that this will run from 
3 to 4$ gallons of oil per hundredweight of metal melted, assuming the metal to be 
“gun bronze.” 

We usually run two heats per furnace per day, although many more heats could be 
run if a larger amount of metal was wanted per furnace. We find it takes 30 minutes 
to 1 hour for preheating the furnace and 30 to 45 minutes to melt the charge. 


DETAILED RESULTS OF INVESTIGATION. 


105 


Furnaces are relined about once a year, and slight repairs are made by us daily 
by use of fire clay and carborundum. 

As to relative advantages and disadvantages of different types of furnaces, we have 
found that for melting the high-copper bronzes and low-zinc bronzes the best results 
are obtained by the open-flame oil furnace, where the entire heat is melted in one 
furnace rather than being distributed among a number of crucibles. If care is taken 
to have the furnace well preheated and to run a flame without excess of air—that is, 
a smoky or reducing flame—and if the metal is poured when it is ready and not held in 
the furnace too long after it has reached the proper temperature, good results can be 
obtained with these furnaces. We have obtained a tensile strength as high as 52,500 
pounds and an elongation of 50 per cent in a number of cases with the regular Govern¬ 
ment “gun bronze,” 88 per cent copper, 10 per cent tin, and 2 per cent zinc, and have 
done work for outside parties in this type of furnace when they had failed to meet 
Government requirements in their own foundries where they employed crucible 
furnaces. When metals containing a large percentage of lead and zinc are to be used, 
there is probably an advantage in the use of crucible furnaces on account of the high 
percentage of volatilization that would occur in a direct-flame furnace with these 
metals of low melting point. For high-heat bronzes we have found no trouble what¬ 
soever from this source. 

We are pleased to note that you are going to study this problem, as we have con¬ 
ducted a number of experiments in our own plant to determine the proper melting 
conditions for the metals that we are usually using, and we have found that practically 
all of the troubles we had been experiencing could be solved by a proper determination 
of the pouring and melting temperatures, the length of time that the metal is heated, 
and the proper control of the air and oil pressure at the furnace. 

Reply 157, subdivision 16. —We use a No. 70 crucible, getting six heats in 10 hours, 
five furnaces per tender; metal 85 per cent copper, 5 per cent zinc, 5 per cent tin, 
5 per cent lead; and 60 per cent copper, 35 per cent zinc, and 5 per cent lead. We 
use 20 gallons of oil per furnace per day. The amount of metal charged varies and 
we keep no record. [If the usual charge of 200 pounds per No. 70 crucible were used, 
the data given above would indicate the quantity of metal charged to be 1,200 pounds 
per furnace per day, or an oil consumption of about 1.7 gallons per hundredweight. 
These data are not included in the tabulation because of the uncertainty as to the 
quantity of metal melted.] 

We have used coal and oil; oil is better as regards the output. The shrinkage is a 
little higher, but the quality of the metal is about the same. Oil is at least twice as 
fast. 

Reply 158, subdivision 7. —We use a No. 60 pot. We have tried a No. 100, but the 
metal cools too much before we can pour it all into our light work. There is a good 
deal of unburned coal in our ashes; the coal is riddled out and used for melting alu¬ 
minum. 

Reply 160, subdivision 20. —We patch burnt-out places on the furnace every day. 

Reply 162, subdivision 1 . —The foundry is small, having only three pits and at the 
present time two molders; one tender takes care of the furnaces and helps the molders 
to pour off and does general work in the foundry. 

If we use a special brand of fire brick much used for blast-furnace linings, the lining 
lasts 10 to 12 months. If, however, we use an inferior fire brick, such as is used for 
ordinary blacksmith forges, the furnace would have to be relined every 5 or 6 
months. 

Our patterns are all small, sometimes as many as 12 patterns being gated together, 
and the gates ofttimes weigh more than the castings. 

The average loss during melting is 3 per cent. 


100 


BRASS-FURNACE PRACTICE IN TUB UNITE!) STATES. 


Our foundry i* thoroughly swept every week; even the shelve* for jiattern*, etc., 
ajv ull thoroughly swept. One of our moldero ha* been in our employ for 30 yean* 
and the other for 25 year*. There are no rule* given to them. 

Reply 163, subdivision 1 .—I have had experience with ull style* of furnace*. Wo 
are not using any furnace* aside from the crucible coke furnace at the present time, 
a* I consider thin the best and most economical furnace for melting non ferrous metals. 

The crucible used is standard size No. 100 special crucible, holding 310 ]>ounds of 
metal. Amount of fuel used per furnace per day, 400 pounds of 72-hour foundry 
coke. Furnaces are relined about every four months, but flues are repaired about 
every four weeks; 2,040 pounds of metal charged per day per furnace. 

The reason we obtain such a low melting ratio of coke to metal is duo to the fact 
that most of the alloys used at this foundry have a rather low melting point, and fur¬ 
thermore the hot crucible is immediately placed into the furnaces again, and in the 
bottom of the crucibles there is a bath of 25 or 30 pounds of metal, and, as you know, 
this arrangement greatly facilitates the melting of additional metals placed in the 
crucible. This ratio of coke to metal melted has been checked and is correct. 

Reply 164 , subdiidsion 26 .—The average time of heat after the first heat in the 
morning is 1 hour and 20 minutes, the first heat taking 2 to hours. 

This plant consists at present of 16 furnaces and is being handled by two men, so 
that one man can take care of eight furnaces. This is one man less than was formerly 
used with oil furnaces of the same capacity. 

As to the number of heats per crucible, at the present time they average only about 
20. However, experiments have been made that prove conclusively that with a 
little additional equipment this life may be brought to 30 or 35 heats. The experi¬ 
ments have been thorough and in a very short time will be applied commercially at 
this plant. 

I can not state definitely how often the furnaces have to be relined. The practice 
at this plant is to make one man responsible for the condition of the furnaces, and 
they are gone over every Sunday and when the lining shows any wear it is patched 
with a mixture of silica fire brick. I do not believe that the actual lining of the shell 
is changed more than once in three months. 

The gas used per hundredweight of metal averages about 3,500 cubic feet after it 
has attained a working temperature, or about 7,000 cubic feet per pot of metal. This 
quantity is dependent upon the composition of the metal used and the temperature 
to which the metal is brought before being poured. The temperature in the pre¬ 
heater is about 600° F. 

The gas, when Pocohontas coal is used in the producer, yields about 120 British 
thermal units per cubic foot and contains about 8 per cent of carbon dioxide, 18 per 
cent of carbon monoxide, 3 per cent of methane, 13 per cent of hydrogen, and about 
58 per cent of nitrogen. 

The metal loss on test conducted recently, averaged from 0.75 to 1 per cent. This 
is considerably less than previously lost w ith oil, but is probably the result of being 
able to obtain a more practical mixture of gas and air on a gas furnace than it is jxissible 
to obtain with oil and air on an oil furnace, so that the furnaces can be operated with 
a reducing flame. 

In considering the above it is well to note that these results mean more when one 
takes into consideration the class of the product. The product of this company con¬ 
sists of numerous very small castings. In some cases the metal is not much mure 
than one-sixteenth to three thirty-seconds of an inch thick, and the gates of a flask 
represent as high as 85 per cent of the entire weight of metal. It is the practice for 
one man to set up 10 to 12 flasks at a time, before pouring. On account of the very 
small castings the metal must be very fluid and have a very high temperature when 
it leaves the furnaces, so that it will have required the fluidity for the last flask. It is 



DETAILED RESULTS OF INVESTIGATION. 


107 


rather an unusual practice and it will no doubt be interesting to know that the tem¬ 
perature of the metal, as it leaves the furnaces, is from 2,200° to 2,300°, the tempera¬ 
ture of the furnaces operating being only about 2,500° to 2,600°. I might also 
add that the spelter and tin are added to the charge after it has been drawn from the 
furnaces. 

Reply 165 , subdivision 9. —Very strong draft. Prefer iiatural-draft furnaces, as in 
them metal is more thoroughly mixed and has closer grain, and there is less shrinkage. 

Reply 166, subdivision 7. —There is very little difference between the quality of the 
metal from various types of furnaces. [This reply was received without address.] 

Reply 167, subdivision 27. —Furnaces constantly repaired. [This reply was received 
without address.] 

Reply 168, subdivision 1 . —[This reply was received without address, and so that 
no further inquiry could be made. The quantity of fuel per furnace is given as 350 
pounds, and the metal melted per day per furnace as 150 pounds, figures that would 
represent a fuel consumption of 233 pounds of coal per hundredweight of metal, a ratio 
that is improbable. As the number of furnaces one furnace tender handles is given 
as four, which is below the normal for this size, it is probable that this foundry has 
four furnaces of this size and that the fuel consumption is given on the basis of all of 
them, or a coal consumption of 58 pounds per hundredweight, a more likely figure.] 

Reply 169, subdivision 32. —The open-flame furnace gives just as good metal as any 
other. We have used it for 10 years on the highest grade of valve work, with com¬ 
plete success. We use pit coal-fired furnaces very rarely in cases where we must get 
a zinc analysis exact to formula. We would not use the open-flame furnace if it did 
not give the highest possible quality of metal for our purposes, as with us quality is 
paramount. 

Reply 170 subdivision 13. —In the open-flame oil furnace the loss of metal due to 
oxidization is large, and poor metal for pressure work is produced. The pit furnace 
in which the crucible is removed and the molds directly poured is best for pressure 
work. Fifty-eight heats for the life of our crucibles is a low figure. We are using 
foreign crucibles, however, not domestic. 

[The makers of this furnace state that the firm supplying Reply 170 at one time gave 
the furnace tenders a bonus of 10 cents per heat for each heat over 50 that they could 
get from a crucible. At that time they were averaging 68 heats per crucible on a 10- 
hour working day. Rush of business made it necessary to run 24 hours a day for a 
short period. During this time the average life of six crucibles, run continually, was 
110 heats per crucible.] 

Reply 171, subdivision 7. —We could make three heats a day. Furnaces are repaired 
■every 25 heats. 

Reply 172, subdivision 7. —We have tried both natural and forced draft on several 
sizes of our furnaces. The results of some tests follow: 


Results of fuel tests with various sizes of crucibles. 


Crucible No.« 

Capacity. 

Fuel per 
hundred¬ 
weight 
with nat¬ 
ural draft. 

Fuel per 
hundred¬ 
weight 
with forced 
draft. 


rounds. 

225 

285 

325 

295 

300 

280 

Pounds. 

31.2; 28. 5 
b 30 
23.7 

Pounds. 

34.5 

38.6 


90 . 

90 . 

20 

95c . 

23 to 28 
31.4 




— mm * 


a All crucibles were special except No. 100. & Average. c a thin-walled crucible. 























108 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


On the No. 90 wo could get four heats per day on forced draft, whereas wo could got 
only three on natural draft. 

The “pinch ” typo of tonga is used. 

Reply 173, subdivisions 33, 37, 40. —Wo use a tilting, open-flame, oil fumaco hold¬ 
ing 2,500 pounds, a stationary rectangular oil-fired reverberatory furnace, holding 
4,000 pounds, and two bituminous-coal reverberutoriea of tho samo general form as an 
ordinary reverberatory copper furnace, holding 7,000 pounds each, with oval hearths 
6 by 8 feet. Wo have no data on the oil consumption in the oil furnac es as they are 
not metered separately from the annealing furnaces. Records for six months show a 
coal consumption of 50J pounds per hundred weight of metal melted in the large rever- 
berutories. The gross melting losses are 2 per cent in both types of oil furnaces, and 
5 per cent in the reverberatory coal furnace. 

There is a largo recovery from the heavy slag formed in the coal furnaces, which 
will bring the net loss figures from all types close together. 

We pour all metal as cold as possible. Our ingots or cakes are largo and heavy. 
Wo have no trouble in pouring them from any of the three different types of furnaces 
in use. 

With oil at a reasonable price, we prefer the tilting, open-flame, oil furnace, and 
if wo were fitting out anew, we would use these entirely. A series of analyses of the 
product for a long period shows maximum variations of about 1 per cent of zinc each 
side of the analysis aimed for, the average variation being very small. With the coal- 
fired fumaco there is no trouble from the metal taking up sulphur. 

Reply 174, subdivision 32. —One furnace tender handles one furnace, which includes 
weighing, charging, mixing, and repairing the lining and ladles, melting on an average 
6,700 pounds per day of nine hours. We repair the lining each day. Our loss is 
1} to 2 per cent on new metal, and 2 to 5 per cent on scrap metal. I have never ob¬ 
served any difference from a physical standpoint with the furnaces we have used. 

Reply 175, subdivision 32. —We find no difference in the quality of metal from the 
different furnaces we have tried. 

The spherical furnace is lined with fire brick 8 inches thick; the egg-shaped one 
is lined with carborundum fire sand 5 inches thick. 

One furnace tender and two helpers handle our four furnaces. Their duties include 
trucking, weighing, charging, distributing, and pouring of metal; also the repairing 
of the lining and ladles. We melt 15,000 pounds per day of nine hours. 

On test, w*e have melted 100 pounds of metal w r ith 2 gallons of fuel oil. 

From tests we have run, w r e found a loss of 1} to 2 per cent in new metal, and from 
2 to 5 per cent in scrap. 

Reply 176, subdivision 50. —We have used only one kind of oil furnace. Do not 
know correct comparison. Oil furnace is cheaper than coke furnace, as coke hero 
in the West is more expensive than Eastern coke, and oil here costs very little as com¬ 
pared to coke; quality of metal seems to be about the same. 

Reply 1 77, subdivision 1. —Coke is the only fuel we have used. We are converting 
one furnace so that natural gas may be used in tests. The cleanliness and rapid 
melting of gas furnaces we think will be advantageous; also less labor will be required. 

Reply 178, subdivision 24. —[Furnace is probably of the 3-burner type. This 
reply was noted on the question sheets and received without address; hence no in¬ 
quiries could be made for further details or to verify the figure for gross loss.] 

Reply 179, subdivisions 28, 32. —We find advantages in using tilting, oil-fired, crucible 
furnaces as against the open-flame furnaces, as the melting loss is lower and the metal 
is more homogeneous. 

Reply ISO, subdivisions 14, 40. —In the forced-draft, tilting, coke furnace we use 
English crucildes. In these we have to coke up every 15 minutes, which makes it 
hard on the melter. The coal-fired reverberatory has a melting chamber about 6 by 
8 inches and can be used for a charge of 1 to 15 tons, according to the amount of sand 





DETAILED RESULTS OF INVESTIGATION. 


109 


put on the melting floor. A 5-ton charge is normal. With a cold furnace we get a 
5-ton heat out in four hours on ingot or scrap manganese bronze. For new metal it 
takes 5 hours. On a 5-ton charge the furnace requires one furnace tender throughout 
the heat, and two other men about one and one-half hours to charge it. The bridge 
lasts 15 heats, the walls 30. 

The gross melting loss on manganese bronze is 3 to 4 per cent. With 20 per cent 
of chips, the gross loss is 5 percent. On gun metal it is 2 percent and the net loss 1 per 
cent. We do not find any trouble from the taking up of sulphur during melting, either 
with manganese bronze or gun metal. We use 800 pounds of coal for a 5-ton heat. 

There is no difference in the quality of the metal produced by either of these types 
of furnace or the natural-draft pit furnace. 

Reply 181, subdivisions 9, 18. —Our crucibles have an outside diameter of 11} inches 
at the bilge. We are just trying out a pit, oil furnace, using low-pressure air, with 
encouraging results. 

[There was a great deal of unburned coal in the ashes from the coal fires at this plant.] 

Reply 183, subdivision 1 . —We are using the round-pit type of furnace made by us; 
36 inches high from the grate bars, with various diameters to suit No. 40, 60, 80, and 
100 crucibles. We use a lining of fire brick and special clay, having a total thickness 
of 4 inches. The cover is oval, 22 inches in diameter, and is made from manganese 
steel. 

We reline our furnaces about every 4 months, also make slight application of special 
clay every 2 or 3 weeks. Our crucibles average 31} heats. 

The undersigned has had experience with almost every kind of furnace except 
electric and has obtained best results in this locality [far West] with the use of 
Washington coke; in the Middle Western States, Lehigh Valley hard coal gave best 
results. 

Reply 184, subdivision 1 . —Have used the oil furnaces where brass or metal is in 
fuel chamber, and no crucible used, and I find it very hard to detect when the metal 
is at the proper temperature at which to pour or tap it. from furnace. It is either not 
fluid enough to make a homogeneous casting, or it is burned. Also it absorbs too 
much oxygen, making castings porous and brittle. The loss in melting will in most 
cases exceed 6 per cent. 

By using the crucible oil burner I find no appreciable difference in metal made 
from a coke pit furnace, except the advantage of rapid melting in the oil furnace 
using crude oil. 

Reply 185, subdivisions 11, 82. —The oil furnace is of the open-flame type, rectan¬ 
gular, about 4 feet 6 inches long by 3 feet 6 inches wide by 3 feet high, outside dimen¬ 
sions. There is a charging door about 2 feet square on the front; directly below this 
is the pouring spout. The furnace is mounted on trunnions and tilted by a handwheel 
and worm gear. The burner is set in the top of the furnace and points directly down 
to the melting chamber. [The inside dimensions and shape of the melting chamber 
were not given.] 

The loss figures [in subdivision 32 of the table] are on 125,000 pounds of metal melted 
in the oil furnace. On 75,000 pounds of metal melted in the oil furnace, which con¬ 
tained 85} per cent copper and 18} per cent tin [rest probably zinc], the gross loss was 
6.3 per cent and the net loss 4.9 per cent. On 50,000 pounds of an alloy consisting 
of 90 per cent copper, 7 per cent tin, and 3 per cent lead, of which three-fourths was 
melted in the oil furnace and one-fourth in the coal furnace, the gross loss was 2.3 
per cent and the net loss 1.1 per cent. The net loss is figured as the gross loss less the 
metal recovered from the slag. The gross loss includes grinding losses, spillings, etc., 
but no correction is made for this in the net figure. 

Reply 186, subdivisions 1, 16. —We use coke melting furnaces and also pit, oil fur¬ 
naces, but will shortly discontinue the use of the latter on account of the increased 
cost of fuel oil. The coke furnaces average 4 heats per day. The oil furnaces average 


110 


UHASS-FUHNACE PRACTICE IN THE UNITED STATES. 


C heats per day, although we have obtained as many as 8 heat* jx»r day. The result* 
mentioned ore based on a 9-hour day. There is no specified time for rclining fur¬ 
naces, we having found it beet to keep up a sort of constant weekly repair. 

The average pxnl crucible gives us about 22 heats, but this is an average of 5 heats 
less than we formerly obtained. 

The number of gallons of oil used has greatly varied, but an average for about 12 
months is 4.665 gallons jx-r heat, and a 19-month averuge of coke used indicates a 
consumption of 69 pounds jx‘r heat. 

At the present time the gas company in the city is preparing two of our furnaces for 
trial purposes, claiming that it is able to get 9 heats a day, and that it has melted 
material at a cost of 5 cents jkt hundredweight. This is by the use of natural gas at a 
price of 30 cents per 1,000 cubic feet. 

Reply 187, subdh mons 28, 82 .—We use two double-chamber, open-flame, oil, tilting 
furnaces, without crucibles, and one crucible, tilting, oil furnace. 

The double-chamber furnaces are oval, the smaller being about 20$ by 48 inches, 
with a melting capacity of 700 pounds for each chamber. The larger are 26 by 63$ 
inches, with a melting capacity of 1,500 pounds for each chamber. The crucible 
furnace takes a 275-pound crucible and has a melting capacity of nearly 800 pounds. 

The lining material for the double-chamber furnaces is a mixture consisting of 57 
per cent silica sand, 29 per cent Duncan clay, and 14 per cent ground graphite crucible 
material, thoroughly mixed and wet with water to the right consistency, to which 
is added one-half pint of silicate of soda to every 2 gallons of water. This lining is 
about 5$ inches thick when the furnaces are newly lined. The crucible furnace is 
lined at present with a special fire brick which came with the furnace, but we expect 
to make all relinings of the same material as wo use in the double-chamber furnaces. 
The fire-brick lining is about 9 inches thick. 

We do not use the waste gases from any of our double-chamber furnaces to heat the 
other chamber not in use and have the passageway between the two entirely closed; 
in consequence we have removed the doors from over the charging holes on these fur¬ 
naces. The charging holes on the larger of these furnaces are 12 inches in diameter 
and on the smaller 10$ inches. We have a much greater melting capacity than would 
meet the demands for castings made in our brass foundry, but we make a great many 
copper castings, the life of which depends on our being able to make them over 99.40 
per cent copper. Likewise we make quantities of high-grade babbitt metals, and have 
found from experience that the only way we cankeepand makethese materials free from 
alloys not intended to be found in them is to keep certain furnaces for certain clas¬ 
sified castings; hence the closing of the passageways between the double-chamber 
furnaces and the removal of the charging doors for escape of gases. 

The specific gravity of the oil used isO.865(31.85° B.); pounds per gallon, 7.21; British 
thermal units per pound, 19,316; British thermal units per gallon, 139,268. All calcu¬ 
lations based on a temperature of 60° F. A 40-pound pressure is used on oil at burner 
and 11 to 13 ounces on air at burner. A special needle-valve burner of our own make 
is used. The discharge orifice of this burner is made by a No. 56 drill; a No. 60 drill 
mounted on the end of an adjustable stem protrudes through the orifice. The oil 
as it passes through the discharge orifice of the burner is compelled to pass through and 
follow the corrugations of the drill, giving it a whirling motion, and the spray, being 
very fine, easily gasifies, and we get a flame that completely fills the volume of the 
furnace and insures perfect combustion. We claim that our loss in melting and 
comparative freedom from oxidation is due largely to this typo of burner. The 
burner that came with the furnaces when first installed discharged a straight stream, 
three-sixteenth inch thick, directly on the metal, and it was a task to take off a heat 
without burning the metal. 

Our furnaces are not metered, and it is therefore impossible to tell the exact oil 
consumption. We use oil for drying purposes in two ingot mold ovens and two corw 


DETAILED RESULTS OF INVESTIGATION. 


Ill 


ovens which are metered. At the end of the month all oil used in excess of that 
shown by the meters on these ovens is charged against our brass-foundry operations. 
We did, however, once make a test of a single chamber of one furnace on copper cast¬ 
ings. We melted nearly 7,400 pounds of copper in seven heats with 105 gallons of oil. 
(hir brass-foundry core oven and one other small oven were also running a part of the 
time during this day, and we have no means of telling just what amount of oil was 
consumed by these ovens. Thus it took less than 1.4 gallons per hundredweight of 
copper. 

Ten hours constitutes the working day in our foundry', but the average time of 
running the furnaces, from starting the fires to taking out the last heat, would probably 
not exceed seven to eight hours on any single day. 

Furnaces are not relined oftener than once in five months. Small repairs around 
charging hole are made every two or three days. 

The average life of a crucible does not exceed 13 heats in our crucible furnace. 

Our heats vary greatly. This is really a jobbing foundry and there are no two days 
alike. Neither our room nor our requirements would permit us to wait until we got 
enough molds made up to equal the capacity of the furnace before casting. We make 
many small heats from our furnaces, by reason of special metal mixtures being required. 
In copper castings it is imperative that all new metals be used. In large bearings, 
where work is extra heavy, we use a mixture consisting of 79 per cent copper, 10 per 
cent lead, 10 per cent tin, and 1 per cent phosphorus. We can use from 20 to 40 per 
cent of scrap in these, provided we have scrap of which we know the alloy content; 
otherwise all new metal is used. We have other castings in which 70 per cent is used. 
We do not use very many borings. 

The average net losses in melting are: For copper castings, 0.85 per cent; brass, 1.6 
percent; and yellow brass, 2.25 per cent. Would recommend coke crucible furnaces 
where large quantities of yellow brass castings are required. We make very' few 
castings of this metal. 

We are very partial to the double-chamber, tilting furnace, without crucible, 
as used in connection with our own type of burner. Its speed in melting, its accessi¬ 
bility, and the low cost of making repairs all appeal to us as being superior to the coke- 
fired furnace. We can not see where castings made from the crucible furnace are in 
any way better than those made from the chamber furnaces. The cost of the crucible 
and the slow melting of the metal in the crucible, it seems to us, militate against its 
use. The present cost of crude oil is about the worst feature of an oil-fired furnace, 
but even in this respect we are confident that the oil-fired furnace, of the chamber 
type, will not consume within 80 per cent of the fuel for melting that the oil-fired 
crucible furnace will consume. Our physical test for oxidation in copper consists in 
bending or doubling a five-eighths inch square, cast-copper, bar casting about 
6 inches long, while heated to a cherry red. If there is any amount of oxidation 
in the piece, it will break on bending. We usually have very little trouble in making 
this test. 

The waste heat from our melting furnaces is sometimes used to heat a large piece of 
scrap brass, too large to be charged into the furnace. These pieces are laid on the top 
of the furnace, over the charging hole, until they become hot enough to break. This 
is the only use we can make of this waste heat. All skimmings, spills, and furnace 
droppings are put through our water tumbling mill, thoroughly washed and cleaned, 
and thrown back into the furnaces. This is a daily routine. 

Reply 188, subdivisions 1, 16, 82 — On the coal and coke furnaces we use a coal bed 
and a coke filling, one-third coal and two-thirds coke being used. Crucibles average 
15 heats in pit; oil furnace, 10 inches in coal and coke. We melt red brass, gun metal, 
phosphor bronze, and yellow brass. 

Our average gross loss on all the alloys we melt, taking all furnaces into consideration, 
is 3§ per cent, including slags, skimmings, etc. 


112 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


Reply 189, subdivisions 10, 18, f9, At.—not** on Reply 17 os to rolling-mill 
furnace tenders.] 

Wo use square, pit, coal-fired furnaces in our rolling-mill melting, and oil furnaces, 
pit, crucible-tilting, and open-flame reverberatory furnaces in running down borings 
and light scrap into ingot. In the 16-inch square (inside) fire we use a pot holding 
240 pounds, having an outside diameter at the bilge of 13$ inches; in the 18-inch fire, 
one holding 460 pounds and with a bilge diameter of 15} inches. We have 10 furnaces 
on a stack. The draft is so strong that we usually reduce the size of the flues in each 
furnace by laying a brick in them. Our egg coal has 12 to 14 per cent ash, runs about 
13,000 British thermal units, and has 0.5 to 0.7 per cent sulphur. We have found 
SO a and CO in cavities in copper and gun metal, but no sulphide S. There is no 
trouble from S or S0 2 in yellow brass. The coal furnaces are relined every 960 heats, 
no patching being done in the meantime. It would probably pay to patch. The 
gross loss on 2 to 1 yellow brass is 1.75 per cent and the net loss 1.25 per cent. The 
net loss on pure copper is 0.5 per cent. 

In the refining plant wo use tilting, oil furnaces, with crucible, which we do not 
like as well as the pit oil furnaces. We also use a tilting, open-flame, reverberatory 
furnace about 6 feet long by 4 feet wide by 3 feet 6 inches high, outside dimensions, 
with a.pouring spout at one end, a burner entering horizontally just above it, and a 
charging door at the top. It is much like an ordinary oil reverberatory furnace, 
only made tilting by mounting on trunnions. This is rated at 500 pounds capacity; 
we usually charge 600 and can get 1,200 pounds in it. One man can handle two of 
these with aid in charging. 

The lining of this is in good shape, after 900 heats, running steadily. We do not 
have our oil furnaces metered and can not tell the oil consumption. The gross melting 
loss in the crucible, pit, oil furnaces, based on oil-free borings, is 5 per cent, in the 
tilting-crucible furnaces 5.5 per cent (the higher figure being due to the double pouring 
into and from a ladle, necessary when a tilting furnace is used) and 10 to 12 per cent 
on the open-flame reverberatory. Notwithstanding this, the open-flame reverberatory 
furnace has such advantage in the matter of speed that we shall in time discard the 
crucible furnaces. We consider this type of open-flame tilting furnace better than 
the more common types. 

We pour as cold as possible in the refining department, but very hot in the rolling- 
mill casting shop, the metal practically boiling. As the mill losses in rolling due to 
defective castings were so high when trying to pour ingots at a low temperature for 
rolling purposes, in order to reduce zinc losses, the cost from that cause far over¬ 
balanced the saving of zinc. 

After the crucibles from the tilting furnaces have become useless through the 
breaking away of the edge, we cut off the top and get a few more heats from them in the 
pit furnaces. 

There would be no difficulty in arranging matters so as to pour directly from the lip 
of the tilting reverberatory, or a similar furnace, into the molds in the casting 
shop of the rolling mill on most castings weighing over 50 pounds, and it could certainly 
be done on a very large proportion of the work. But the zinc loss in this type is too 
great to make this practical with oil or gas fired furnaces. 

Reply 190 , subdivision SO. —Furnaces are repaired 'weekly. 

We believe that our oil consumption amounted to about 3,000 gallons to every 
50.000 pounds of metal melted. We don’t know the relative oil consumption of the 
large and small furnaces. We could get as many heats from the big furnace as the 
little ones. The life of the crucible was just the same in the small as in the large 
furnace. 

We believe the oil furnace has a tendency to burn the metal. The principal dis¬ 
advantage, besides the difficulty in buying oil at a fair price and the procuring of 


DETAILED RESULTS OF INVESTIGATION. 113 

proper labor, is the uncertain results owing to the amount of loss from apparently 
no cause whatever. 

[The air pressure was given as 10 pounds and the oil pressure as 80 pounds, but the 
make of burner used is said by the maker to be designed for an air pressure of 4 to G 
ounces and an oil pressure of 40 pounds. In response to an inquiry on this point, it 
was stated that the figures given were correct. The high oil consumption and the 
tendency to burn the metal may thus be due to operating the burner under conditions 
for which it was not designed.] 

Reply 191 , subdivision 32. —Our test showed an average of 1 gallon of oil used to 49 
pounds of metal charged into furnace. Oil was metered by a f-inch piston meter. 
During our test of three days we ran four heats per day, although we often run five 
heats from a furnace. Actual time from lighting of furnace until shut-off of blast on 
last heat was 7% hours. We have to reline these furnaces three times a year, and 
ordinarily do a little patching each week to keep them in perfect working condition. 

Some of our pouring crucibles (No. 35), used as ladles, last only three or four days, 
on account of breakage, whereas others last much longer; however, we believe that 
about 450 pots of metal is the average active life of a crucible; we use them for pour ing 
only. 

We know of no positive difference in physical tests, pressure tests, or behavior in 
the foundry between the metal from our present furnaces and from the old coke 
furnaces. 

Reply 192, subdivisions 10, S3. —[Reply 192 was not sent by the firm whose practice 
it represents, but the data were given by another firm to which they had been given by 
a representative of the first firm. These figures show the net loss on 2-to-l yellow 
brass for different casters as 1.44 per cent, 1.55 per cent, and 1.60 per cent; the net 
loss on yellow brass, including one-fourth of an alloy consisting of 90 per cent of cop¬ 
per and 10 per cent of zinc, as 1.30 per cent; on pure copper and some 90-to-10 brass, 
0.59 per cent. Thirty pounds of coal and coke per hundredweight is used for yellow 
brass, and 36 pounds on 90-to-10 brass and copper. The crucibles last 35 heats on 
yellow brass and 8 heats on copper. The gross loss on yellow r brass is about 3 per cent, 
1 to 1.5 per cent being recovered from the ashes and skimmings. 

An open-fiame, oil furnace is also used on 2-to-l yellow brass, and the net loss in 
this is 3.4 per cent. It is said that there are two distinct opinions in this plant as to 
the over-all economy of the open-fiame furnace. It is reported that the chemical staff 
is against and the practical millmen favor its operation. Still later reports indicate 
that the use of the open-flame furnaces at the plant has been entirely abandoned.] 

Reply 193, subdivision 9. —We have tried producer gas in a large unit, but found it 
unsuccessful owing to oxidation. 

Reply 194, subdivision 10. —As to the fuel consumption, with No. 65 and with No. 
70 crucibles, as near as we can estimate, this is practically the same. Of course we 
get more metal from the No. 70, but it takes a trifle longer to melt and perhaps a little 
more coal. We have never figured the matter out as fine as this. 

As to the life of crucibles, our average for the year 1912 was 58.98 heats per crucible. 
We think you will find this average considerably higher than any other average you 
will get, as we understand from the crucible makers we get a longer run than anyone 
else, evidently due to the method of handling. 

As to the size of our No. 65 crucible, it is 10| inches at the top, Ilf inches bulge, 
7 J-inch bottom, and 15 inches high. The size of the fire at the bilge of the crucible is 
practically 14 inches square. 

The furnace is built somewhat larger at the top and tapered at the bottom, but of 
course after a few months’ use in punching the fires, the bottom gets considerably 
larger. 


44712°—Bull. 73—16-8 



114 * BRA88-FURNACE PRACTICE IN THE UNITED STATES. 


Regarding hum 1 ling of crucible®, wo have had a good deal of experience with tho 
handling, and have found out that by careful use and preparation tho life of crucibles 
tan be considerably prolonged. Tho details of this wo do not taro to give out. 

As to the building of tongs, they have considerable to do with this also, and think 
we had rather not discuss tho matter. 

[Admission was not granted to this plant.] 

Reply 195, subdivision 5 .— Oil furnaces burned the metal. 

[This reply was noted on the question sheets, without address, so that no inquiry 
could bo made as to the astonishingly low figures for melting losses, which are 
probably incorrect.] 

Reply 196 , subdivision St. —We make a very light class of brass castings, containing 
10 per cent of zinc, a casting often weighing only a fraction of an ounce. We are able 
to get our 10 per cent zinc metal hot enough to run such castings, poured from a ladle, 
with the open-flame oil furnace, with an average gross melting loss of 4$ per cent, 
using about one-fourth borings or very light scrap and three-fourths gates or ingots. 
We do this by maintaining a strongly reducing flame and by getting the heats out just 
as quickly as possible. 

We melt a red brass which is lower in zinc content for these light castings in a very 
small crucible in pit fires, because we can not get this higher melting alloy hot enough 
to be transferred to a ladle without getting too cold to bo poured before the ladle is 
empty. We prefer the open-flame oil furnace to any other for our light work with the 
10 per cent zinc alloy. 

Reply 197 , subdivision 1. —We have and use occasionally two crucible oil furnaces 
which are very satisfactory, except the cost of fuel oil in New York City. 

Reply 198 , subdivision S3. —The furnace is rectangular, 10 feet 6 inches long, 5 feet 
5 inches wide, 4 feet 9 inches high, with 3 chambers 28 inches long, 18 inches wide, 
and 33$ inches high. Lining of fire brick, 9 inches thick. Cover is rectangular, 
36 by 24 by 4 inches. Framework of structural steel, covered with lirc-brick dabs. 
Nos. 100, 60, and 40 crucibles are used. No burner is used, as tho pan system is 
employed with a natural draft obtained from an 80-foot stack. Approximately 1 
gallon of fuel oil is used per hundredweight of metal. The furnace is relined about 
every 15 months, slight patching being done every 2 weeks. Average life ot cru¬ 
cible is 15 heats. Gross lass during melting 2.1 per cent; 2.05 per cent net is the loss 
during melting, taking account ot all metal recovered. 

Reply 199, cubdii'ision 8 .— Both round and square furnaces are used; figures for 
both lumped together. 

Reply 200. subdn'tsion 10. —[See notes on Reply 17 regarding furnace tenders.] 

The figures on coal and coke (62 J pounds) are based on 100 pounds of metal. This 
may seem high, but it combines the brass and German silver, the latter comprising 
most of our melt. 

Reply 201 , subdhisions 2 , 24. —The figures for gross losses in melting on both the coke 
and the gat. furnaces are on one week’s run of turnings. Other figures are averages 
for regular practice. 

Our experience has shown that the gas furnaces have tho following advantages over 
the coke furnaces: (1) Reduction of melting cost, owing to: (a) Cheap gas fuel in this 
district; (6) rapidity of melting; (c) longer life ot lining; ( d) elimination of coke and 
ash handling and storage; (f) ease of recovery of metal from broken and leaking cru¬ 
cibles; (/) small volatilization loss due to shorter meltingtime; (2) increased efficiency 
of tenders, owing to less exposure to the heat because of absence of coking and poking. 

The advantage of the coke furnace is the longer life of crucibles and the absolute 
reliability of fuel supply, although this last item has not been of importance, as our 
gas supply has been uninterrupted for a period of two years. The physical properties 
of the metal are identical in both methods of melting. 


DETAILED RESULTS OF INVESTIGATION. 


115 


The “pinch” type of tongs is used. 

Reply 202, subdiinsion 89 .—The furnace is a reverberatory furnace, similar to a mal¬ 
leable-iron melting furnace, except that the metal hearth is shorter and deeper. The 
furnace is rectangular, 18 feet long, 5 feet wide, and 6 feet high, outside dimensions. 
The coal and combustion chamber is 5 feet from end of furnace to bridge wall, inside 
measurements, but the inside width of furnace is 3£ feet. 

The metal chamber is 9 feet long by feet wide, inside. Beyond the metal cham¬ 
ber is another chamber 3 by 3£ feet, inside, which leads to stack. The tap hole is 2 
feet above the floor. Furnace is fired with melting coal, mechanical stoker, with top 
and bottom blast, being used. 

Lining: Sides, 9-inch fire brick; bottom, silica sand, 18 inches deep in lowest part. 
Cover: Fire-brick bungs, 5 feet by 18 inches wide. The fuel used is Pennsylvania or 
West Virginia melting coal—same coal as we use in our malleable furnaces. Average 
analysis of coal: Moisture, 1 per cent; volatile matter, 34 per cent; sulphur, 0.7 per 
cent; fixed carbon, 59 per cent; ash, 6 per cent; 13,500 to 15,000 B. t. u.; pressure at 
fan, 11 £ ounces. 

When running two heats a day, which we generally run, one man tends the furnace. 
His duties are to charge the metal into the furnace, fix furnace up for next heat, wheel 
up coal, take out ashes, break up and pick metal from slag, take castings over to the 
tumbling barrels, clean up floor, etc. 

Usually two heats per day are made, except Saturdays, when we run one heat per 
day, working only till noon. When crowded, we run three heats per day. When 
we run so slack that 300 pounds of metal or less is required, only one heat is taken off. 
The working hours of the furnace are 10 hours a day of two heats; it is relined about 
once every two years. 

The net percentage of loss during melting, taking account of metal recovered from 
all metal-bearing refuse, was, 1909 , 2.55 per cent; 1910, 1.57 per cent; 1911, 2.58 per 
cent; 1912, 2.93 per cent. The melting-loss and fuel-consumption figures are based 
on records for 3,000,000 pounds of red brass. 

The chief advantage of this furnace is low cost of melting and operation. We do 
not think that the metal from this furnace is quite as clean as from crucible furnaces, 
and would not use this furnace if we were making a very high-grade bearing bronze. 
However, we get a good grade of metal, and the castings machine up very clean. We 
have no record of physical or pressure tests. 

Touring takes about 20 minutes to one-lialf hour for every heat. 

Reply 203, subdivision 1 .—[See notes on Reply 17 relative to rolling-mill furnace 
tenders.] 

The crucibles we use have the following dimensions: Outside diameter of top, 10| 
inches; inside diameter of top, 8$ inches; outside diameter of bilge, 12 inches; height 
over all, 16£ inches; height inside, 142 inches; capacity, about 200 pounds of nretal. 

The fuel we use is a good, medium-hard porous, 48-hour coke, burned under natural- 
draft stack. 

One furnace tender can handle 10 furnaces. He is assisted by three helpers, a 
pot puller, mold ringer, and mold cleaner. 

Furnaces are relined about once in four months, and minor repairs are made as 
required. 

The average yearly melting loss is 1.68 per cent gross. 

Average analysis of German silver: Copper, 62 per cent; nickel, 15 per cent; zinc, 
23 per cent. 

Average analysis of phosphor bronze: Copper, 95 per cent; tin, 5 per cent. 

We make no brass. 

For foundry work nearly every type of furnace can be made to yield good results, 
whether reverberatory, tilting, with or without crucible, or pit furnaces using crucibles; 
but for ingots required for rolling there is no doubt in my mind of the superiority of 


116 


BRA88-FURNACE PRACTICE IN THE UNITED STATES. 


melting in crucible* with natural draft, taking precaution* to preserve the metal from 
the action of the air a* completely a* jHxwible. 

We consider coke far better than coal for our work. Coal would bo too slow. 

Open-flame oil furnace* are all right on phosphor bronze that i* not to bo rolled 
down to leas than 0.2 inch thick. If such metal is rolled down to 0.05 inch there is 
trouble. 

Two-ton soft-coal reverberatory furnaces are satisfactorily used in Wales on 2-to-l 
yellow brass, with a melting loss of 4 per cent. There is no trouble from not getting 
the proper analysis nor from pouring by means of a ladle. 

Reply 204, subdivisions 1 , St .—The open-flame furnace has a double chamber. It 
gives a very uneven mixture and a large percentage of oxidation. 

Our previous figures giving the proportion of coke used to metal melted were in 
error. I arranged to keep a careful record of one day’s ojierations with our eight 
furnaces, with the following results: 

Record of one day's operation with eight furnaces. 


Furnace No. 

1 

2 

3 

4 

5 

6 

m 

7 

8 

Metal melted. 


444 

455 

416 

577 

386 

261 

192 

164 

Coke used. 


n 

2P3 

2*12 

342 

233 

256 

152 

162 

Coke used per hundredweight of metal... 


60 

67 

62 

59 

60 

98 

79 

99 


A total of 2,895 pounds of metal was melted with 1,937 pounds of coke, or about 
66 pounds of coke to 100 pounds of metal. 

I am unable to give the percentage of loss in melting separately for coke and oil 
furnaces. 

About 0.4 per cent of our melt is yellow brass, the rest red brass or leaded bronze. 

We estimate the oil consumption per 100 pounds of heavy scrap melted to be 1 to 1J 
gallons. 

[The above figures represent an average melt per furnace per day of only 362 pounds, 
or less than 2 heats per furnace, against the normal estimated speed of 4 heats per 
day reported in the table (subdivision 1). Thus the furnaces were not used to capacity, 
a practice that may account for the low fuel efficiency. It is to be noted also that 
furnaces 6, 7, 8, with only a single heat per day, or in the case of No. 6, with probably 
two small heats, show much poorer results than those running on 2 or 3 full 
heats. Five ounces is an unusually low oil pressure for an open-flaipe furnace.] 

Reply 205, subdivision IS .—[The data for reply 205 are not taken from a reply to the 
list of questions sent out, but are tabulated for comparison from a paper by Hughes. 0 

The gross melting loss on an alloy consistimg of 85 per cent copper, 10 per cent 
tin, and 5 per cent lead, is given as 0.9; on one consisting of 84 per cent copper, 
5 per cent zinc, 8$ per cent tin, and 2} per cent lead as 0.8 and 0.9; on pure copper 
as 0.8 per cent, and on an alloy consisting of 58 per cont copper and 42 per cent zinc 
as 2.9 per cent. The proportion recoverable from skimmings is given as 0.75 per cent. 

The coke used showed the following analysis: Carbon, 89.24 per cent; sulphur, 
0.86 per cent; ash, 9.35 per cent; moisture, 0.55 per cent. The pressure on the 
forced draft was 1$ to 2 ounces. The crucible life is the average on 45 crucibles.] 

Reply 206, subdivision 1.—We prefer hard coke to gas-house coke. Most of our 
output is an alloy consistimg of 87 per cent copper, II per cent tin, and 2 per cent 
zinc, but about 10 per cent is an alloy consistimg of 70 per cent copper, 26 per cent 
zinc, and 4 per cent lead, so that the average composition of tho total melt for which 
fuel and loss figures are given will be about that of a red brass with 3 per cent of zinc. 

a Hughes, G., Nonferrous alloys in railway work; Jour. Inst. Met., voL 6, 1911, p. 9C; Metal Ind., voL 
9,1911, p. 426; Castings, vol. 9, 1911, p. 13. 
























DETAILED RESULTS OF INVESTIGATION. 


117 


MISCELLANEOUS DATA. 

[The data contained in many replies were so meager owing to absence of records 
that the conditions were not sufficiently defined to make the data comparable with 
those tabulated. Such replies appeared to be chiefly from small foundries using 
coal or coke furnaces. "What data could be gleaned from these, as well as some frag¬ 
mentary data collected on visits to plants that did not give complete replies, are 
presented below.] 

A. —Round pit coal furnaces used; No. 10 to No. 60 crucibles; 2 heats in 10 
hours; crucible life 30 to 35 heats. Have tried gas, but find it hard on crucible. Coal 
is easier on crucible and costs less. 

B. —Round pit forced-draft coal furnaces used; No. 25 and No. 40 crucibles; 4 heats 
in eight hours; average crucible life, 25 heats; coal used per furnace per day, 150 
pounds; furnaces relined every two months; all ingot metal used; bronzes of varying 
composition. 

C. —Wo have been running our brass furnaces, which are of the ordinary pit-furnace 
type, for several years with the ordinary chimney draft, and have had rather poor 
results. About a couple of months ago we changed some of our furnaces and put 
a suction draft on them by coupling an exhauster to the chimney. This resulted 
in great improvement over the old way of running the furnaces, in that we may get 
from 5 to G heats a day, whereas before the change we had difficulty in getting 
3 heats. However, we have not run these furnaces long enough to be able to give 
exact results that would be useful in a publication such as you anticipate making. 

D. —Round pit oil furnaces used; 18 inches inside diameter, 26 inches deep; No. 
65 to No. 100 crucibles; oil burner takes oil at 32 pounds; a small proportion of 
compressed air at 30 pounds is used to spray the oil; air at low pressure for combus¬ 
tion; combustion air preheated in horizontal flue. One man handles our four fur¬ 
naces. The furnaces are used only for our own repairs and renewals. 

E. —Natural-draft pit furnace used; No. 40 crucible; charge 60 to 100 pounds; 2 heats 
a day; crucible life 30 to 35 heats; reline once a year; melting loss 1 to 2 per cent, 
according to heat and composition. 

F. —Round pit coal and coke furnace used; No. 40 crucible; 2 to 3 heats in eight 
hours; furnaces relined or repaired every six months; crucible life about 30 heats. 

Q .—Natural-draft pit coke furnace used; 36 inches deep, 18 inches inside diameter; 
No. 60 crucible. 

//.—Tilting oil furnace used; No. 60 crucible; air and oil pressure each 4 to 6 
pounds; 7 heats a day. 

J.—Natural-draft coke furnaces used; No. 18 and No. 25 crucibles in three furnaces; 
No. 50 cruciblo used in one. We melt yellow brass. 

/.—Round natural-draft coke furnaces used; 36 inches deep, 16 inches inside 
diameter; No. 20 to No. 80 crucibles; 2 heats in 10 hours; 50 to 90 pounds of coke 
per furnace per day; 100 to 200 pounds of metal per furnace per day; furnaces relined 
once a year; use waste heat to heat a core oven. 

X .—Round natural-draft coke furnaces used; 18 inches inside diameter; No. 40 to 
No. 60 crucibles; 2 heats in 10 hours; furnaces repaired as needed; rebuilt every 24 
months; average crucible life, 20 heats. 

L .—We use only round coke furnaces; fire-brick lining; diameter inside of lining, 
20 inches; 22 inches deep; cast-iron cover. 

We melt only nonferrous, white metals. Capacity of each furnace, 2,000 pounds 
per day of nine hours. Gross loss from oxidation, 1£ per cent. Redeemed from 
skimmings, about one-half of the gross loss, leaving the net loss about 0.75 per cent. 

)/ —Coal furnace used; No. 50, No. 60, and No. 70 crucibles; 2 heats in 9£ hours; 
crucible life 12 to 25 heats. 


118 BRA88-FUBNACB PRACTICE IN T11E UNITED STATES. 


.V.- Wo noto that 0 omo of your questions refer to tho utilization of waste heat from 
brass-melting fumacet. Thin matter hart boon in the writor’i mind for Homo two or 
three yearn, and there certainly in a chance for very great Having in the average brass 
foundry. 

Some three years ago we were operating 20 pit furnaces, using hard coal as fuel, 
and at that time we ran for about one week a test that showed stack temperatures at 
various times during the day The writer has endeavored to locate the records of this 
test, but his search fails to reveal them. However, it is very clear that the result of 
the test showed that between the hours of 9.30 a m. and 5.30 there was heat enough 
escaping through our stack to represent approximately 150 steam horsepower. We 
did not figure this ourselves, but we had a local engineer go over this matter for us, t 
and he assured us of these figures. 

Within the last 12 or 18 months, we have steadily changed from our pit furnaces 
using hard coal to various types using fuel oil. We are at present using about 3,000 
gallons of fuel oil per week, and it is obvious that if there is any means of utilizing the 
waste heat the saving will be worth while. 

We can not give you dimensions of our furnaces as we have various sizes and rcline 
them according to the class of work that we are running, which also determines the 
size of pot that we use for melting. 

Size of crucible varies according to the grade of work handled in the foundry. 
When we are running light work we melt in No. 40 or No. 60 crucibles; when running 
heavy work we melt in No. 80 or No. 100 crucibles. This refers to the pit furnaces. 
In our one tilting furnace we use a No. 275 crucible. 

The coal is burned with natural draft. We have a stack about 70 feet high, which 
gives us very good natural draft. 

Our oil burners were first installed on a high-pressure system which operated under 
10 pounds of air and 10 pounds of oil. On account of the extreme noise of this system, 
we have recently started to change over to low pressure which we find just as economi¬ 
cal and much more quiet. On the new system our air is operated with about 6 to 10 
ounce pressure, and the oil at 10 pounds. 

One operator can handle throe to four furnaces, according to the number of heats 
required per day and the size of pots used. 

Burners consume approximately 45 gallons of oil per day on the average in 8 or 9 
hours. 

Number of heats which we take from our furnaces will vary from 4 to 6 per day. 

We run our furnaces between 8 and 9 hours per day on the average. 

Our furnaces are relined approximately every two months. This period varies, 
however, according to the service to which they are subjected. Besides this we 
patch our linings approximately once in two weeks. For patching we use a mixture of 
half common fire clay and half carborundum fire sand. This mixture is moistened 
with water and a small percentage of silicate of soda. 

Crucibles last approximately 30 heats on brass. They last longer in the oil furnace 
when using low-pressure air than when using high. 

O. —Coal furnace used; repaired yearly; crucibles No. 16 and No. 18, 4 heats per 
day of 9 hours; crucible life 30 heats. 

P. —Two round furnaces used; 12 by 20 inches and 14 by 22 inches; gas-house coke; 
No. 14, No. 18, No. 40, and No. 70 crucibles; from 3 to 7 heats [probably from both 
furnaces together] in 9 hours; relined every six months to one year; crucible life 33 
heats. 

Q. —Natural-draft coke furnace used; crucible holds 30 to 60 pounds; life about 40 
heats. 

R. —[A brass rolling mill replies as follows.] 

Wo use entirely round fire-brick crucible furnaces, fired with anthracite coal, 
melting all sorts of copper alloys, ranging from pure copper to 60 per cent copper and 
40 per cent zinc; also various grades of German silver and cupro nickel. 


DETAILED RESULTS OF INVESTIGATION. 


119 


In regard to the matter of round as compared with square melting furnaces, the 
square furnaces are a little easier to build and maintain, as they can be laid up with 
ordinary brick, whereas the round furnaces require special tile. If properly handled 
there is little difference between the fuel consumption of the two types; in fact, we 
have no figures indicating a direct comparison with the round furnace. We believe 
it is easier to be sure of not using an excessive amount of fuel when we have one kind 
of alloy being melted always in the same size crucible. Where it is necessary to vary 
the size of the pots and to use various alloys having different heats of pouring there 
is very little to be gained in using the round fires. The round fire carries a uniform 
thickness of fuel all the way around the pot. The square fire carries the fuel mostly 
in the corners. 

I think you will be able to see from the above that the question as to which kind of 
fire uses the most fuel depends entirely upon the proportioning of the size of the furnace 
to the size of the pot, and, also, as to the condition of repair in which the furnaces are 
kept. 

[Later, in conversation during a visit to this plant, the statement was made that 
properly porportioned round furnaces were found by actual test to be more econom¬ 
ical of fuel than properly proportioned square furnaces.] Five-tenths per cent of 
the melt is recovered from the ashes. Draft, 2 inches of water at base of stack. 

S. —[Another rolling mill visited used square furnaces, No. 60 crucibles, hard coal, 
and natural draft. Separate flues ran to the main stack from every three furnaces, 
to equalize the draft. No records were kept. The estimated net melting loss was 
1.5 per cent on yellow brass and 0.75 per cent on German silver. The operator esti¬ 
mated that 25 pounds of coal per 100 pounds of metal melted was used. lie stated 
that it was possible to pour metal for heavy rolling ingots from small crucibles into 
a larger one and from that into the mold, and consequently that on a good deal of 
rolling-mill work it would be possible to melt in large quantities and to pour the 
metal satisfactorily if there were some way of melting a large quantity without too 
much loss of zinc. The temperature drop in the double pouring was thought to be 
more objectionable than the danger of oxidation.] 

T. —[Another rolling mill visited has tried tilting-crucible furnaces with a capacity 
of 900 pounds, fired with cold producer gas. This type had been abandoned because 
of the high expense for upkeep of crucibles, etc., but not because of the zinc losses, 
although these were higher than in the square, coal-fired, pit furnaces now being used. 
With much of the rolling-mill work there is no trouble in pouring by means of a ladle 
and probably all of that kind of product could be so poured. One representative of 
this firm had the impression that the solution of the problem of melting yellow brass 
will be the use of a one-half to 4 ton reverberatory furnace fired with producer gas. 
He stilted that in England a 1-ton, soft-coal reverberatory is used for brass, composed 
of 60 per cent of copper and 40 per cent of zinc, with the avowed object of getting 
more perfect alloying, a lower zinc loss, and a composition varying less from that 
desired, than can be obtained in small crucibles. 

The chemist of this firm stated that according to his estimates the figure of 7,500 
pounds of zinc lost per day up the stack of the rolling mills of Waterbury, Conn., as 
given by Parsons« should be nearer 15,000 pounds, and that he estimates that in 
Waterbury the total daily zinc losses, including those in pickling, are over 20,000 
pounds.] 

U —Square furnaces used; inside dimensions, 18 by 18 by 30 inches; fuel, 72-hour 
uncrushed coke, crushed at foundry with hammer to proper size to fit snug; No. 30 
to No. 150 crucibles used, all in same size furnace; metal put in crucible before 
putting in fire; no metal added while in fire; No. 125 crucible holds about 250 pounds 
charged in this way; crucible life 12 to 18 heats; various bronzes melted; no data 
kept on metal losses or fuel consumption. 


a parsons, C. L., Notes on mineral wastes: Bull. 47, Bureau of Mines, 1912, p. 21. 






120 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


We \i(*e open-flame oil furnaces, with capacities rated at 500 and 1,000 ]>ounds 
and natural-draft pit coke furnaces with No. 100 crucibles. 

Theoil is*‘distillate,’' and has a fpecifie gravity of about 0.87. It is fed at a 20-pound 
pressure, the air pressuro being 8 to 10 ounces. We inelt an average of 4,000 ]>ounds 
in an 8-hour day in all furnaces, one tender handling them all. Wo can get up to 8 
heats in the oil furnaces, which are relined every three months. In tho coko furnaces 
the crucibles average 30 heats. We use 2 gallons of oil per hundredweight of metal 
melted; no data on coke. The gross melting loss (alloy not given, but probably red 
brass] is about 5 per cent, but we have no definite data. Tho open-flame oil furnace 
is best for speed, and the coko furnace for tensile strength, although we have remarka¬ 
bly good results on tensile strength with the open-flaine furnace. 

If'.—[A gas company replies as follows:] 

The tests on melting brass with city gas were unsatisfactory. The gas consumption 
was low’ enough but the loss was over 10 per cent, and we believe that this w as due to 
our ignorance of the furnace and its operation. However, we are going to try to run 
some further tests and take advantage of the experience gained in the first tests. 

In test runs with this furnace in another city the loss was very low’. We believe that 
with proper operation of the furnace our loss will also be low. In this case we shall 
be able to melt brass cheaper than w ith either coal, coke, or oil at the present market 
prices for those fuels. 

A'.—N atural-draft pit coke furnaces of two sizes and forced-draft tilting coke furnaces 
are both used. The pit furnaces are all 36 inches in depth; those for the No. 70, No. 
100, and No. 150 crucibles are 19 inches inside diameter, and those for No. 300 are 25 
inches inside diameter. The tilting furnaces are 31 inches deep, 23 inches inside diam¬ 
eter, and take a special crucible holding about 400 pounds. A little anthracite coal 
is used w ith the coke. The following data are lumped for both types of furnaces, no 
separate data being at hand: 

One furnace tender handles five furnaces, getting an average of 3 heats in a 10- 
hour day. Tho fuel consumption is 75 pounds of coke and 8 pounds of coal per hun¬ 
dredweight of metal melted. The average crucible life is 27 heats, and the gross melt¬ 
ing loss is 2.7 per cent. Furnaces relined twice a year. There is no great difference 
in the quality of metal from the tw’o types of furnaces. The forced-draft tilting fur¬ 
naces are not hooded, and give off objectionable zinc smoke into the foundry. 

DISTRIBUTION OF FURNACES REPRESENTED IN REPLIES. 

• 

In all, 28 States wero represented by the replies listed in tho table. 

In tho 63 replies on natural-draft coke furnaces 18 States were 
represented; half of the replies were from Pennsylvania, Ohio, and 
Michigan, the rest being from widely scattered States. Over half 
of the replies on square pit coke furnaces wero from Pennsylvania, 
and all but one of tho others wero from adjacent States. 

The four replies on forced-draft pit coko furnaces wero from four 
widely separated States. 

Of the dozen replies on forced-draft tilting coko furnaces, one- 
third were from Pennsylvania, one-third from New York, and the 
other four replies from four different States. 

Of the 49 replies on natural-draft anthracite-coal furnaces, 80 
per cent wero from New England or tho Hudson River Valley, only 
12 per cent being from firms outside of New England and New York. 
Of tho replies on square coal furnaces, 75 per cent w*ero from Con¬ 
necticut. Of tho replies on forced-draft pit anthracite-coal fur¬ 
naces, 90 per cent were from tho Chicago district. 


DETAILED RESULTS OF INVESTIGATION. 


121 


The three replies on soft-coal reverberatory furnaces wero from 
three States. 

Three replies on city-gas furnaces represented two States, whereas 
replies on natural-gas furnaces were all from Ohio and Pennsylvania^ 
over two-thirds being from Ohio. 

The oil furnaces show the widest distribution, 33 replies on pit oil 
furnaces being from 13 States, and 31 on tilting oil furnaces from 15 
States, whereas the 40 replies on open-flame oil furnaces were from 
18 States. The six replies on oil-fired roverberatories came from 
five States. Oil furnaces of all classes were represented by 24 of the 
28 States from which replies were received. 

To summarize, the oil furnaces appear to be the most widely dis¬ 
tributed, the coke furnaces being next. The natural-gas furnaces are 
of course localized. The hard-coal furnaces, particularly the square 
natural-draft furnaces and the forced-draft pit furnaces show re¬ 
markable localization, as do the square pit coke furnaces. Locali¬ 
zation of the square, natural-draft furnaces is due to the conservatism 
of the rolling-mill industry; localization of the forced-draft, pit, and 
the square, pit, coke furnaces is probably due to the success of the 
firms first using those types in certain localities. 

OUTPUT OF DIFFERENT TYPES OF FURNACES. 

The pit furnaces reported outnumber the tilting furnaces, but 
considering the larger capacity of the tilting or tapping furnaces of 
all types and the larger size of the firms using tilting or tapping fur¬ 
naces, it is probable that the output of all but yellow brass from those 
types is considerably larger than that from pit furnaces. However, 
the general use of pit furnaces by the rolling mills on their large out¬ 
put will cause the greater part of the total of all brasses and bronzes 
melted to be from pit furnaces. 

Although there are a third more replies on oil furnaces than on 
coke furnaces, and nearly twice as many as on hard-coal furnaces, 
the use of hard coal by so many of the large rolling mills will probably 
make the output melted by coal equal to or greater than that melted 
by oil. As so many of the firms using coke run a large number of 
furnaces, it seems probable, on the basis of the replies received, that 
the quantity of metal melted by coal, by coke, and by oil will not bo 
greatly different. 

TYPES OF PLANTS REPRESENTED. 

Jobbing shops, with rare exceptions, use pit furnaces, the crucibles 
holding less than 300 pounds. A few of the large manufacturing 
plants, outside of the rolling mills, still use pit furnaces, but these 
are, almost without exception, those whose castings are so small or 
so thin that the drop in temperature due to pouring into a ladle from 
a tilting or tapping furnace can not be allowed. The great majority 


122 brass-furnace practice in the united states. 

of the manufacturing plants whose aim is largo production use tilting 
or tapping furnaces on account of their greater speed. Few of the 
users of tilting coke furnaces, tilting crucible oil furnaces, tilting 
open-flame oil furnaces, or reverberatory, oil-fired, or coal-fired 
furnaces come into the jobbing class. Most of the large manufactur¬ 
ers, except the rolling mills, uso oil on account of the great speed of 
melting possible with its use, and in this connection it should be noted 
that the open-flame, oil furnaces seem to come the nearest to meeting 
the needs of the large manufacturer who must melt huge quantities 
of red brass. 

TYPES OF ALLOYS MELTED. 

All of the commercial types of furnaces, with proper handling, are 
largely and successfully used in melting bronzes, red brass, and other 
alloys low in zinc. On account of the volatility of zinc, the furnaces 
mostly used for yellow brass and manganese bronze are of types that 
do not involve the passage over the surface of the metal of large vol¬ 
umes of products of combustion at high velocity; that is, natural-draft 
coal or coke furnaces are more largely used for high-zinc alloys than 
forced-draft furnaces, crucible oil furnaces coming next, and open- 
flame oil furnaces or reverberatories last. 

However, on alloys containing 15 to 20 per cent of zinc ( u lialf 
yellow, half red”) the open-flame oil furnaces are largely used. In 
these the great speed of melting compensates to a largo extent for 
the metal loss, when all the cost factors are considerd. The proportion 
of zinc volatilized from a given weight of metal melted will depend 
on the temperature to which the metal is raised, which is chiefly 
determined by the size and nature of the mold into which the metal 
is to be poured, the extent of molten-metal surface exposed, the 
total time the metal is held at a high temperature, and the rapidity 
with which the zinc vapor is sw'ept away by the stream of gases 
(products of combustion) flowing over the surface of the metal, as 
the main variables. Hence, great speed of melting may compensate 
for rapid flow of gases, for although a considerable amount of zinc 
may be swept away in a given time, yet the volatilization of a rather 
great weight of zinc per unit of time for a short time only may mean 
a lesser percentage of the total melt than a smaller weight vola¬ 
tilized per unit of time over a much longer period. 

On “half yellow, half red” alloys the balance seems to be in favor 
of rapid heating of large charges even with rapid gas circulation, 
the percentage of zinc volatilized probably being less than with slow 
heating of small charges; that Is, at the vapor pressure of alloys con¬ 
taining around 20 per cent of zinc, great speed of melting will out¬ 
weigh the effect of the rapid current of gases of combustion necessa¬ 
rily formed in obtaining the high melting speed. 

On yellow' brass or manganese bronze, with a zinc content of 30 
to 40 per cent, the melting losses reported on the furnaces involving 


DETAILED RESULTS OF INVESTIGATION. 


123 


rapid flow of waste gases show in general a larger zinc los6 than in 
those with less rapid flow and slower heating. This result does not 
necessarily mean that the oil or gas furnaces, of either crucible, open- 
flame, or reverberatory types, may not be more economical in the 
long run, even on alloys high in zinc. 

From the point of view of an engineer, the efficiency of a furnace 
is the ratio of the heat units absorbed by the metal in useful work 
to the heat units supplied in the fuel. What a foundry superintend¬ 
ent means by “the efficiency of a furnace” is not heat efficiency 
alone, though that is a factor, but cost efficiency. On a cost- 
efficiency basis the most efficient furnace is the one that shows the 
lowest total cost, per pound of metal melted, for fuel, metal lost in 
melting, bad castings due to metal spoiled by the furnace, upkeep, 
repairs, labor, interest, and overhead charges; at the same time the 
furnace must produce, from the alloy melted, metal of a satisfactory 
quality and in quantities suitable for the purpose of the foundry. 

Any one factor may throw a furnace entirely out of consideration 
for a particular foundry. If a certain fuel is not readily obtainable 
in a certain locality, furnaces using that fuel do not enter into that 
foundry’s choice. If a certain furnace has a much higher first cost 
than another less efficient furnace, a firm of small capital may not 
be able to invest in the more efficient type. If a plant is located 
in the heart of a city, where space is at a premium, it may be neces¬ 
sary to install a furnace requiring less floor space than a more efficient 
type. Again, a jobbing foundry requiring small quantities of a large 
number of alloys may be forced to use a larger number of smaller and 
less efficient furnaces than would a large manufacturing plant needing 
large quantities of one kind of alloy. 

There is also a distinction between the efficiency of a furnace and 
the efficiency of its use. A furnace, if properly handled, may be 
capable of turning out metal with low fuel consumption, low repair 
or crucible cost, and low loss in melting, and yet may be so used as to 
be in all these respects distinctly inefficient, whereas another furnace, 
at its best, may not be capable of as good a performance in these 
respects as the first furnace at its best, and yet, if more “fool-proof, ” 
may give better results. Hence, one must consider not only efficiency 
under ideal conditions, but how readily ideal conditions can be 
obtained in the use of various types. 

The problem does not concern the furnace only; the real problem 
is the economical production of molten metal of a satisfactory 
quality. The comparison is not merely one of furnace A and furnace 
B, but of foundry procedure with furnace A and foundry procedure 
with furnace B. 

In order to get the proper point of view, then, it will be well to 
consider the general problem of combustion, and some properties of 
brass in their application to the general problem. 


124 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


GENERAL FACTORS 


A 


FFECTING OPERATION OF 
FURNACES. 


HR ASS 


COMBUSTION. 

One pound of carbon burned to carbon dioxide (C0 2 ) gives 14,540 
British thermal units, hut if burned only to carbon monoxide (CO), 
it gives only 4,380 British thermal units, or only about 30 per cent 
of its full value. Oil burned to CO gives about 60 per cent of its full 
value.® Therefore, as regards heat development, the more complete 
the combustion is, the better. However, to obtain complete com¬ 
bustion to C0 2 , it is ordinarily necessary to supply considerably 
more than the theoretical proportion of oxygen, twice the theoretical 
being considered fair boiler-room practice. 

All the excess air has to be heated to the temperature of the 
escaping products of combustion. In boiler-room practice the aim 
is to get no CO, or only traces, with the least possible air excess. 

OXIDIZING AND REDUCING ATMOSPHERES. 

In brass melting the air excess must be kept low enough to give a 
flue gas that is not sufficiently oxidizing, when it comes in contact 
with the metal, to produce appreciable oxidation. Copper, zinc, 
tin, and lead, the constituents of commercial brasses, are all readily 
oxidizable at the temperature to which they have to be heated for 
melting and pouring. Oxidation not only results in loss of metal, 
actually burning it to a dross that has to be skimmed off, but any 
oxides that do not happen to separate well and are not skimmed 
off are taken into solution by the metal or are mechanically held by 
it. These are a source of weakness in the metal and may cause it to 
fail under hydraulic test, owing to its porosity due to oxide inclusions. 
It is always recognized that it is essential to prevent or to remedy 
oxidation. The prevention usually comprises a layer of charcoal 
over the metal, which produces a layer of carbon monoxide directly 
over the surface; the remedy is deoxidation,, as by phosphorus or 
boron suboxide, or by zinc or manganese contained in the charge 
itself. 

It is almost certain that carbon monoxide is harmless to molten 
brasses and bronzes. It is even more certain that oxygen is harmful, 
whereas carbon dioxide may be inert or may be oxidizing. It is 
oxidizing to zinc. 

All melters strive to maintain a “reducing atmosphere” and to 
avoid an “oxidizing atmosphere” over the metal. Just how high 
in carbon monoxide and low in oxygen the gases have to be to show 
the beneficial “reducing atmosphere” and how low in carbon mon¬ 
oxide and high in oxygen they have to be to form the harmful oxi¬ 
dizing atmosphere is unknown, as no systematic study of the furnace 
gases from brass furnaces has been made. 


a Krom, L. J., Development of melting furnaces: Metal Ind., vol. 7, 1909, p. 2S9. 




FACTORS AFFECTING OPERATION OF BRASS FURNACES. 125 


Demesse ° and Grebel 6 suggests passing the products of combustion 
over molten lead, and states that if the gases are oxidizing the lead 
will be covered with a film of oxide; if the gases are reducing, the 
surface of the lead will be bright. 

It is certain, however, that the carbon monoxide must be so high 
and the oxygen so low that one can not, in ordinary furnaces, hope 
to maintain a sufficiently reducing atmosphere without sacrificing a 
good many heat units through the burning of carbon to CO instead 
of to C0 2 . 

VOLATILITY OF ZINC. 

In dealing with zinc-containing alloys, the volatility of the zinc is 
also a factor. Pure zinc boils at about 920° C. (about 1,690° F.) c 
and has a very appreciable vapor pressure at a temperature not far 
above its melting point, 418° C. (785° F.). 

Molten copper-zinc alloys, owing to the high vapor pressure of 
zinc, lose zinc readily at high temperatures. Some rolling mills cast 
yellow brass at a temperature very close to the boiling point, holding 
the crucible in the furnace until signs of actual ebullition arc observed. 
One foundry making “half yellow, half red” sand castings of such a 
size and shape that they are extremely thin and difficult to run docs 
not pour the metal until the furnace tender can feel the metal “jump ” 
when an iron bar is poked into the melt; that is, when the metal is 
almost at the boiling point. 

In such cases the loss of zinc is readily apparent, the volatilized 
metal burning to clouds of white zinc oxide as soon as it reaches the 
air. Even at much lower temperatures considerable zinc fume is 
evolved. 

The rate of loss of zinc depends on the vapor pressure of the zinc in 
any given composition of brass at various temperatures, on the maxi¬ 
mum temperature reached, on the rate of heating to this temperature, 
on the volume and velocity of the gas flowing over the surface, that 
is, on how nearly equilibrium is reached between melt and vapor, and 
on the rate of diffusion of zinc from the body of the melt into tho sur¬ 
face that is losing zinc. 

Tho temperature required is fixed by the size of tho casting to be 
made and by tho material of tho mold. The vapor pressure of the 
brass used is fixed by a natural law, as is tho rate of diffusion. Hence 
tho only variables over which the foundryman has any control are 
(1) tho rate of heating to tho proper poiuing temperature, (2) 
whether tho metal is taken from the furnace as soon as it is ready or 
allowed to wait there or allowed to get too hot, so as to require 

a Demesse, J., Le comburimdtre: Rev. Chem. App., vol. 2,1013, p. 99; Chera. Abs., vol. 7,1913, p. 3254. 
b Grebel A., La comburimMrie des combustibles gazrux: Le Genie Civil, vol. 01,1912, p. 200. 
e Let'hatclier, II., Tho measurement of high temperatures, 1912; translated by G. K. Burgess, p. 43S; 
Barus, C., The pressure variations of certain high-temperature boiling points: Phil. Mag., ser. 5, vol. 29, 
1890, p. 141. 



126 BRASS-FUKNACK PRACTICE IN THE UNITED STATES. 

cooling, ami (3) the volume and rate of flow of gases over the surface 
of the metal. 

With a given rate of flow of gases through the furnace, it Is obvious 
that the more rapid the rate of heating, the less the zinc that can ho 
carried off as vapor by the gases. On this point the statements given 
in the notes on Replies 8, 15, 140, and 201 aro of interest. With a 
given rate of heating, it is clear that the less the volume and the less 
rapid the flow of gases over the metal, the less is the loss. In a fur¬ 
nace closed absolutely tight, with no passago of gas, thero would bo 
no loss of zinc, after the small quantity had been given off that Is 
necessary, at the furnace temperature and pressure, to saturate the 
vapor spaco existing in the furnace, no matter how long the metal 
might bo held in the furnace. Electric heating is the only known 
method of heating that will approach this ideal condition. 

'Whether the gas flow or the rate of heating has the more powerful 
influence will depend on the vapor pressure of the alloy melted. 

VAPOR PRESSURE OF MOLTEN BRASS. 

Little accurate information is available on the vapor pressures 
of the copper-zinc alloys. 

Hansen® made some measurements of the vapor pressures of two 
brass alloys, ono of which contained 76 parts copper and 24 parts 
zinc, and the other, 55 parts copper and 45 parts zinc,'with the fol¬ 
lowing results: 

Vapor pressures developed by two brass alloys at various temperatures. 

COPPER 76 PARTS, ZINC 24 PARTS. 


Temperature.* 

Pressure 

developed. 

•C. • F. 

1,000 1,830 

1,084 1,985 

1,150 2,100 

Atmospheres. 
0.29 
0.66 
1.18 ■ 


COPPER 55 PARTS, ZINC 45 PARTS. 


900 

1,650 

0.24 

950 

1,740 

0.44 

1,000 

1,830 

0. 72 

1,100 

2,010 

1.55 


« In these results, an allowance for possible error of ±15° for centigrade readings and of ±30* for Fahren¬ 
heit readings should be mode. 

Theso data are plotted in figure 1, the plot being made to show 
both the average values and the limits of accuracy given by Hansen. 
The curves aro approximately parabolic in form. 


a Hansen, C. A., Electric melting of copper and brass: Trans. Am. Inst. Metals, 1912, p. 111. 













FACTORS AFFECTING OPERATION OF BRASS FURNACES. 127 

Interpolating on those curves, the boiling point (vapor pressure at 
1 atmosphere) of the alloy containing 76 parts copper and 24 parts 
zinc is 1,130° C. (± 15°), or 2,070° F. (± 30°), and of the alloy 
containing 55 parts copper and 45 parts zinc, 1,040° C. (± 15°), or 
1,905° F. (± 30°). 

Hansen’s work was done in a vacuum electric furnace, at constant 
temperature, and observation of the boiling point was made possible 
by altering the pressure. By his method the temperature is calcu¬ 
lated from the power consumption of the furnace, a method that 
can not give close temperature figures, as considerable latitude is 
left to the operator in his decision as to just what pressure corresponds 
to actual boiling. 



PRESSURE, ATMOSPHERES 


Figure 1.—Vapor pressures of copper-zinc alloys. (Plotted from Ilansen’s data.) The curves show 
how the partial pressure of the zinc vapor—that is, the tendency of the zinc to volatilize—increases as the 
temperature increases, and, for the two cases shown, illustrates the fact that for any given temperature 
the higher tho zinc content the higher the vapor pressure. The vertical lines through the plotting points 
show the limits of accuracy (±25° C.) that Ilausen gives for his determinations. Note that the alloy with 
24 per cent of zinc has to be raised to 1,100° C. to become as volatile as is that with 45 per cent of zinc 
at 1,000° C. 

In an unpublished communication Ilansen states that with an 
alloy consisting of about 81 per cent of copper and 19 per cent of 
zinc, there was gentle movement of the melt at 1.05 atmospheres, 
and at 0.94 atmosphere globules of metal shot up more than 8 inches 
above the surface of the melt. 

Tho boiling point was taken as 0.95 atmosphere. The power 
consumption was equivalent to a temperature of 1,300° C. (±15°), 
or 2,370° F. (±30°). This would give about 1,310° C. (±15°), or 
2,390° F. (±30°), as the boiling point at 1 atmosphere. 

Fery a gives a curve for the “fractional distillation” of an alloy 
consisting of 63 per cent copper and 37 per cent zinc, which shows a 
flat part between 1,030° and 1,100° C. or 1,885° and 2,010° F. This 
observation was made with a radiation pyrometer and may bo low, 

a Fery, M., Determination despointsd’ebbulition de cuivre et do zinc: Ann. chim. phy., 7th ser., vol. 28, 
1903, p. 428. 





























































































128 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


owing to deviation from “black-body radiation” and to zinc fumes 
between tho melt and the pyrometer, cutting down the radiation. 
The observations were taken very rapidly, tho rate of heating (an 
electric-arc furnace was used) being over 1,000 ° C. in 7 minutes, and 
hence is probably not extremely accurate. 

J. M. Lohr, of the Bureau of Mines, has obtained a few hitherto 
unpublished approximate figures as to tho boiling points of various 
copper-zinc alloys by heating tho alloys in an electric-resistance fur¬ 
nace. Observations of time and temperature were made, tho tem¬ 
perature being read with a base-metal thermocouple immersed in the 
metal without protecting sheath, tho boiling point being taken as 
tho beginning of an approximate flattening of tho tune-temperature 
curve. Tho results of tho tests were as follows: 

Boiling points of various copper-zinc alloys. 


Composition of alloy. 

Boiling point.o 

Copper. 

Zinc. 

Per end. 

Pn end. 

•C. 

•F. 

84.5 

15.5 

1,365 

2. 490 

77 

23 

1,220 

2,230 

75 

25 

1,220 

2,230 

74.5 

25.5 

1,220 

2,230 

67 

33 

1.120 

2,050 

65 

35 

1,100 

2,010 

56.5 

43.5 

1,050 

1,920 

55.5 

44.5 

1,050 

1,920 


« Allowable error ± 20° for centigrade readings, and ± 40° for Fahrenheit readings. 

S. J. PopofT, at Cornell University, found that an alloy that was 
about 82 parts copper and 18 parts zinc boiled at 1,300° C. (±25°), 
or 2,370° F. (±50°). 

None of tho boiling-point figures is to be taken as final, but they 
will servo to give an idea of tho approximate shape of tho curve. 
The boiling point of copper was determined by Greenwood a as 2,310°C. 
(4,100° F.), and Burgess h gives tho boiling point of zinc as 920° C. 
(1,690° F.). Tho figures on boiling points from tho above sources 
aro plotted in figure 2, together with the melting-point curve as 
determined by Shepherd.® The figures may not represent true 
boiling points, but they at least show the temperature at which a 
very rapid volatilization of zinc occurs. 

The vapor-pressuro curve for any given alloy will not have its 
origin at the melting point of that alloy, but somewhat below it. 

Bcngough and Hudson d determined the rate of volatilization of 
zinc from a sample of brass consisting of 70 per cent of copper and 
30 per cent of zinc. The sample was annealed for 2£ hours at 920° 

o Greenwood, n. C., The boiling points of metals: Trans. Faraday Soc., vol. 7, pt. 2, 1911, p. 151. 

5 Burgess, G. K., Measurement of high temperatures, 1912, p. 438. 

c Shepherd, E. 8., The constitution of the copper-iinc alloys: Jour. Phys. Chem., vol. 8,1904, p. 423. 

<* Bcngough, G. D., aud Hudson, O. F., The heat treatmeat of brass: Jour. Inst. Metals, vol. 4,1910, pp. 
101,110. 












COPPER, PER CENT. 

Figure 2.— Approximate boiling points and assumed pouring temperatures of copper-zinc alloys. The 
melting-point, curve is from Shepherd. The pouring temperature is assumed at 150° C. above the 
melting point, and the approximate boiling-point curve is plotted from all available data, the limits 
of error given by the various workers being shown by the length of the vertical lines through the plotting 
points. The boiling points of purecopperand pure zinc are the figures of Greenwood and Burgess,respec¬ 
tively. The nearer tne pouring temperature to tho boiling point, the greater the vapor pressure of zinc 
and Sts tendency to volatilize. Note that the alloys containing 30to 40 per cent of zincare poured wheu 
very close to the boiling point; those containing 20 percent of zinc, when about halfway net ween the 
melting and the boiling points; and those containing 5 per cent of zinc, when only al>out a quarter of the 
way between the two points. These relations show why the loss of zinc and the trouble from “brass 
shakes” are higher in connection with brasses containing 30 to 40 percent of zinc than inalloyscontaining 
lower proportions. 


44712°—Bull. 73—1G-9 























































































































130 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 

to 930° C. ( 1 ,690° * *to 1,705° F.). At the end of this time tlio outer 
one sixty-fourth of an inch of the bar had lost 5.7 per cent of zinc 
(nearly 20 per cent of the original proportion of zinc). On being 
annealed for 1 hour longer at 930° C. (1,705° F.), the outer one sixty- 
fourth of an inch lost 4.7 per cent of zinc; in another half an hour 
at 900° C. (1,050° F.), it lost 1.4 per cent, and in a half hour more, 
at 700° C. (1,290° F.), 0.5 per cent. Below a depth of one-sixteenth 
of an inch the loss was negligible, but the high loss from the outer 
ono sixty-fourth of an inch shows that the vapor pressure is still 
appreciable, even with a temperature as low as 700° C. 

Turner ° heated a small quantity of brass, consisting of 63 per 
cent of copper and 37 per cent of zinc, to a temperature just above 
the melting point of copper (1,082° C.; 1,980° F.) for half an hour, 
in a high vacuum (about 0.007 atmosphere). All the zinc distilled 
off;: at 1,200° C. (2,190° F.) there was only a slight volatilization of 
copper.. The lead in an alloy containing 7 per cent of that metal 
was completely distilled off at 1,200° C. in a vacuum. 

In a vacuum (pressure of about 0.0001 atmosphere) ho obtained 
tho first sign of sublimation of pure zinc at 375° C. (700° F.). With 
an alloy consisting of 60 per cent of copper and 40 per cent of zinc, 
tho temperature above which sublimation occurred was 520° C. 
(970° F.); and with an alloy consisting of 70 per cent of copper 
and 30 per cent of zinc, sublimation occurred at 550° C. (1,020° F.). 

Bassett 6 states that in annealing yellow brass there is no appre¬ 
ciable volatilization of zinc at 450° C. (840° F.); that volatilization 
becomes noticeable at 500° C. (930° F.); that at 550° C. (1,020° F.) 
0.3 gram per square meter is lost in 10 hours; that at 650° C. (1,200° 
F.) 1.5 grams per square meter is lost in 1 hour and 5.4 grams in 10 
hours; and that at 750° C. (1,380° F.) 46 grams per square meter is 
lost in 1 hour and 63 grams in 10 hours. 

Damar(*ay c observed faint signs of volatility of zinc in a vacuum 
at 184° C. (363° F.) after 50 hours. 

However, as vapor-pressure curves for tho full range of temperatures 
are not available, it may bo assumed for purposes of comparison that 
the difference in temperature between tho melting and the boiling 
points of a brass of any given composition, will determine the sig¬ 
nificant part of tho vapor-pressure curve. 

It is ordinarily necessary to pour brasses and bronzes at a tempera¬ 
ture of 100° to 200° C. (180° to 360° F.) above tho melting point, in 
order that the mold may fill properly and the metal bo free from 
blowholes. Lolir d found this to bo the case in casting small test 
bars in heated graphite molds. 

o Turner, T., Behavior of certain alloys when heated in vacuo: Jour. Inst. Metals, vol. 7,1912, p. 105. 

t> Bassett, W. II., Zinc losses: Jour. Ind. Eng. Chem., vol. 4, 1912, p. 164; Metal Ind., vol. 10,1912, p. 239. 

e Damarpay, E., Sur la vaporisation des m^taux dans le vide: Compt. Rend., vol. 95,1882, p. 183. 

* Lohr, J. M., The tensile strength of the copper-zinc alloys: Jour. Phys. Chem., vol. 17,1913. p. 23. 




FACTORS AFFECTING OPERATION OF BRASS FURNACES. 131 

Bassett® puts the pouring temperature of “high” or yellow brass 
(copper and zinc ratio, 2:1), which melts at about 915° C. (1,680° F.), 
at 1,050° C. (1,920° F.), whereas tho chemist of another rolling mill 
uses 1,065° C. (1,950° F.) as the pouring temperature of this alloy. 

Carpenter and Edwards b recommend pouring castings of alumi¬ 
num bronze consisting of 90 per cent of copper and 10 per cent of 
zinc at 80° C. above the melting point. 

Karr c gives 910° C. (1,670° F.), as tho pouring temperature for a 
sand casting of a brass made of 69 parts of copper and 31 of zinc, 
lie gives 893° C. (1,640° F.) as the observed melting point of this 
brass, but states that the true melting point is 950° C. (1,742° F.). 
He used a radiation pyrometer and tho observations were probably 
affected by deviation from black-body radiation. 

Primrose d gives 1,100° C. (2,010° F.), as a good pouring tempera¬ 
ture for gun metal consisting of 88 parts copper, 10 parts tin, and 2 
parts zinc. 

Longmuir, quoted by Karr/ Buchanan/ and Law o gives, as a 
suitable pouring temperature for gun metal, 1,070° C. (1,960° F.); 
for an alloy consisting of 75 per cent of copper and 25 per cent of zinc, 
1,020° C. (1,870° F.); and for brass containing 60 parts copper and 
40 parts zinc, 975° C. (1,785° F.). 

Another pouring temperature given for gun metal is 2,300° F. 
(1,260° C). h 

A brass consisting of 75 per cent of copper and 25 per cent of zinc 
melts at about 920° C (1,670° F.), and one consisting of 60 per cent 
of copper and 40 per cent of zinc at about 890° C. (1,635° F.). The 
melting point of gun metal, consisting of 88 parts of copper, 10 parts 
tin, and 2 parts zinc, as determined by Norton,* is about 995° C. 
(1,825° F.). 

Keardonl gives 2,000° F. (1,095° C.), as tho pouring temperature 
(from the ladle) of one lot of an alloy consisting of 73 parts copper, 18 
parts zinc, 7J parts lead, and If parts tin, and 2,175° F. (1,190° C.), 
as the pouring temperature of another lot of the same alloy. This 
alloy will probably melt at a temperature of about 920° to 925° C. 
(1,690° to 1,700° F.), as Norton k found that an alloy consisting of 

a Bassett, W. II., loc. cit. 

t> Carpenter, II. C. II., and Edwards, C. A., Production of castings to withstand high pressure: Engineer¬ 
ing (London), vol. 90,1910, p. 871; abstracted in Jour. Inst. Metals, vol. 5,1911, p. 327. 

c Karr, C. T., The pouring and melting points of some high-grade bronzes: Trans. Am. Brass Founders’ 
Assn., vol. 5, 1911, pp. 72, 77, 80. 

d Primrose, II. S., Metallography as an aid to the brass founder: Metal Ind., vol. 8,1910, p. 466. 

« Karr, C. P., loc. cit. 

/ Buchanan, J. F., Practical alloying, 1910, p. 37. 

g Law, E. F., Alloys, 1909, p. 10. 

A See answer to question in “Shop Problems”: Metal Ind., vol. 10,1912, p. 428. 

i Gillett, II. W., and Norton A. B., The approximate melting points of some commercial copper alloys; 
Technical Paper 60, Bureau of Mines, 1913, p. 8. 

J Reardon, W. J., The manufacture of high copper castings: Metal Ind., vol. 8, 1910, p. 212. 

* Gillett, II. W., and Norton, A. B., loc. cit. 




132 


BBA88-FUBXACE PRACTICE IN T1IK UNITED STATES. 


75 parts of copper, 20 parts of zinc, 2 parts of tin, and 3 parts of load 
melted at a temperature of about 920° C. (1,690° F.). 

On the assumption that commercial copper-zinc alloys are poured 
when 150° above their melting points, the pouring temperatures of 
such alloys have been plotted in figuro 2. It will bo noted that 
for a zinc content of 40 to to 30 per cent, which includes Muntz 
metal, ordinary yellow brass (copper-zinc ratio, 2:1), and brass 
containing 70 parts of copper and 30 parts of zinc, and covers 
the zinc content of manganese bronze, although in that alloy the 
presence of iron, tin, aluminum, and manganese may alter the boiling 
point, the pouring temperature and boiling point of a given alloy 
as indicated by the curves aro only about 25° to 35° C. (50° to 70° F.) 
apart. As the zinc content is decreased from 30 to 20 per cent, the 
curves begin to separate, until, with an alloy containing 18 per cent 
of zinc, the pouring temperature and boiling point aro 135° C. apart. 

These relations show why it has been found perfectly feasible to 
melt metal with a zinc content of 16 to 18 per cent in open-flame, 
oil furnaces ° for at this percentage the vapor pressure of zinc is 
probably not much over half an atmosphere at the pouring tempera¬ 
ture, whereas, on a 2-to-l brass, it is nearly 1 atmosphere. Hence, 
with the 18 per cent alloy, the speed of melting in the open-flame 
furnace just about balances the effect of the greater volume of gas 
passing over the metal. 

When the percentage of zinc is down to 5, as in ordinary red brass, 
although the presence of the tin and lead may complicate the vapor 
pressure relations somewhat, the vapor pressure of the zinc is so low 
that a small gain in speed of melting more than compensates for a 
greater gas flow that may bo necessary in order to obtain that speed. 

Longmuir 6 seemingly does not consider that the vapor pressure 
of a brass lias anything to do with the proportion lost, as he states that 
the loss of zinc is a function of the temperature reached and not of 
the proportion present in the alloy. To substantiate his position, he 
gives the following figures: 


Zinc losses in melting certain alloys. 


Name of alloy. 

Highest 

tempera¬ 

ture 

reached in 
furnace. 

Zinc in 
alloy. 

Zinc con¬ 
tent lost 
from 
sample. 

Calculated 

loss of 
zinc from 
whole 
melt.c 

Red brass. 

*F. 

2,386 

2,160 

2,144 

1,900 

Per cent. 
10.2 
26.0 
1.8 
40.5 

Per cent. 
28.6 
26.1 
27.7 
19.0 

Per cent. 

2.9 

6.8 

0.5 

7.7 

Yellow brass. 

Gun metal. 

Muntz metal. 



o See Replies 2 and 104 in subdivision 33 of the table; also Hansen, C. A., Electric melting of copper and 
brass: Trans. Am. Inst. Metals, voL 6, 1012, p. 113. 
b Longmuir, P., Deoxidation of copper ana its allovs: Foundry, vol. 40,1912, p. 460. 
e Calculated from Longmuir's figures in two preceding columns. 
















FACTORS AFFECTING OPERATION OF BRASS FURNACES. 133 


Beforo accepting LongmuiEs conclusion it would seem to be neces¬ 
sary to know something as to the type of furnace used, the length 
of time each alloy was in the furnace, and whether all the melts were 
under the same conditions. 0 

PRESSURE OF GASES FLOWING OVER MELTING METAL. 

Aside from the speed of melting, the pressure, the volume, and the 
velocity of the gases flowing over melting metal should he considered 
in regard to the loss of zinc. 

Replies 2, 86 and 104 state that in open-flame oil furnaces melting 
alloys consisting of 16 to 18 per cent of zinc, the operators close the 
vents to the furnaces as much as possible in order to maintain a 
pressure over the metal higher than atmospheric. This procedure is 
now advocated in the catalogue of the makers of one furnace of this 
type, who say: 

In a paper entitled “On the Behavior of Certain Alloys When Heated in Vacuo,” 
read by Prof. Thomas Turner at the London meeting of the Institute of Metals, Jan¬ 
uary 16-17, 1912, the author showed that zinc could be removed from brass and other 
alloys very rapidly by heating in a vacuum. 

The results obtained in melting yellow brass in our furnaces seem to prove that the 
converse of Prof. Turner’s experiment is also true; namely, that when alloys high in 
zinc are melted under pressure, the tendency of the zinc to volatilize is lessened and 
the melting loss is lowered. While the pressure on the interior of the furnaces during 
melting, with the charging door closed, is not very great, it is sufficient to lessen the 
volatilization of zinc in the metal being melted. Melters have frequently noticed 
that if the pouring spout of the furnace is slightly enlarged their melting losses are 
greater. 

In a closed system, with equilibrium between melt and vapor, 
increase of pressure would of course drive back some of the vapor 
into the molt. 6 But the furnace must have some vent; hence it is 
not a closed system, and the problem is the effect of increase of 
pressure in the vapor phase on the rate of volatilization of zinc. 

Stefan, 0 quoted by Ewan d and Mellor, 0 gives a formula for the 
relation between the speed of volatilization of a liquid in an inert gas 
with the partial pressure of the gas, the formula and derivation being 
as follows: 

V=C log J 

in which— i>=speed of volatilization 

c =a constant 

P=prcssure of gas and pressure of vapor 
partial pressure of vapor 

a A letter to Mr. Longmuir requesting information on these details was unanswered. 

b Compare with editorial reply to question regarding oxidation difficulties: Foundry, vol. 41,1913, p. 120. 

c Stefan, J., Sitzungsber. d. k. Akad. d. Wias. zu \V ien, vol. 68,1878, p. 38. 

d Ewan, I., Ubcr die Oxidationsgeschwindigkeit von I'hosphor, Schwefelund Aldehvd: Zeitschr. phys. 
Chem., vol. 16, 1895, p. 319. 

e Mellor, J. W., Chemical statics and dynamics, 1904, p. 310. 

/ The logarithm is tho natural, not the Briggsian logarithm 







134 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


Let p 2 -»pre88ure of gas. 

Then P*Pi+jPa 

and t>«-c log 

v - e ,u ®(£ +1 )- 

From tho above it will be seen that the rate of volatilization will 
decrease as tho prossuro of the inert gas increases, other conditions 
remaining the samo. 

Xo data are available on the value of c, nor of or p 2 for the case 
in hand. However, in order to got some idea of the magnitude of 
the effect, it might bo assumed that at a pouring temperature of 
1,1 G0° C. for an alloy consisting of 80 parts of copper and 20 parts of 
zinc, under equilibrium, the partial pressure of tho zinc vapor will bo 
0.8 atmosphere. However, equilibrium is by no means reached, 
both because the gases are not fully saturated with zinc and because 
of the probable slowness of diffusion from tho zinc-rich body of the 
melt into the zinc-poor surface. Were equilibrium established as to 
all the gases passing through tho furnace, practically all the zinc 
would bo lost. 

Let it be assumed, then, that the partial pressure of zinc vapor is 
0.05 atmosphere under the conditions in tho furnace. With that 
assumption, the ratio of tho rates of volatilization of zinc with increase 
in the pressure of tho waste gases passing through the furnace from 1 
atmosphere to 1.5 could bo calculated as follows: 


V 0 c I'v'( " i"’+l) 


V 0 log 1.05 . 04879 
V, log 1.033 .0:1278' 


or a ratio of 1:0.67. 


A lesser increase in tho gas pressure will of course result in a lesser 
saving of zinc. As tho partial pressure of zinc vapor increases, the 
ratio of decrease of rate of loss of zinc to increase in pressure of waste 
gases increases; thus, the higher tho percentage of zinc in tho alloy, 
the greater tho relative saving resultant on increase of the pressure 
of inert gas. 

Henco it would appear that the improvement shown practically by 
increase of pressure in this type of furnace is in agreement with tho 
theory. 

Tho principle is of course applicable to all types, but tho open- 
flamo furnace is more easily closed so that an appreciable pressure 
can bo maintained than are other types of fuel furnaces. 

It should perhaps be pointed out that the increased pressure 
referred to above is that in the melting chamber over the metal, not 
that on the air supply to the burner, as high-air pressure on the bur¬ 
ner appears to be detrimental, because it increases tho velocity of 





FACTORS AFFECTING OPERATION OF BRASS FURNACES. 135 

the gases and also renders the maintenance of a reducing flame more 
difficult. The increased pressure in the furnace chamber should be 
obtained by reducing the size of the opening at the pouring spout by 
having the burners fit tightly into the furnace and by keeping the 
charging door closed as much as possible. 

VELOCITY OF FURNACE GASES. 

It should be remembered that the evil effect of increase of the 
velocity of the gases passing over the metal is doubtless greater than 
the good effect of increase of pressure, so that pressure should not be 
sought at the expense of much increase of velocity. The gases do 
not become saturated with zinc vapor, but are continually taking it 
up. The less zinc vapor already in the gases the faster it is taken up. 
Hence, if the gases are passing through the furnace at a high speed, 
volatilization of zinc is increased, just as the wash hanging on the 
clothesline dries more quickly on a clear, windy day when the 
humidity is low, than they do on a still, damp day. For each fuel 
there is a lower limit to the speed with which the gases may travel 
through the furnace, as each fuel, in developing enough heat units 
to get the heat out at a given speed, must develop a certain volume 
of gases, and this must pass out. Hence proper gas velocity is insepar¬ 
ably connected with the volume of products of combustion produced 
from the various fuels. 

Were the speed with which a given quantity of metal can be 
melted with various fuels and the volume of waste gases produced the 
same in all cases, the furnace design that would give the lowest zinc 
loss would be the one in which the gases moved the slowest. Again, 
too, a rapid rate of passage of hot gases through the furnace affords 
too short a time for them to give up their heat to the metal, resulting 
in slow melting and low fuel efficiency, more of the heat being carried 
out with the waste gases than is the case with a lower gas velocity. 

De Ileen® has found that on passing a gas current over a liquid 
surface the speed of evaporation increases with increase in tempera¬ 
ture more rapidly than does the vapor pressure of the liquid. The 
amount of liquid evaporated was found to increase with increasing 
velocity of the gas passed over it, the relation between weight of 
liquid evaporated and velocity being expressed by the equation 



where II is a constant, S is the weight of liquid evaporated, and V is 
the speed of the gas current. 

It is probable that molten metals follow the same general laws in 
regard to speed of vaporization as do liquids. 

« De Ilcen, M., La ritcsse de vaporisation des liquides: Jour, chera. phys., vol. 11, 1913, p. 205; chem. 
abstr., \ol. 7, 1913, p. 3438. 





13G 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


VOLUME OF FLUE GASES FROM VARIOUS FUELS. 

Tho main variables affecting the loss of zinc in melting brass that 
are under any control by varying the type of furnace or the fuel used 
are the speed of melting—that is, the time given for volatilization— 
the velocity with which the flue gases pass over the surface of the 
metal (rapidity with which gases unsaturated with zinc vapor are 
brought to the metal), and the volume of these gases per unit of 
metal melted for different fuels. With a given speed of melting, the 
greater the volume of the gases the greater tho velocity with which 
they must pass over the metal; hence, with a given melting speed, 
the fuels giving the greater volume of flue gases per unit of metal 
melted give a greater tendency to zinc loss from both the velocity 
and the volume factors. About 144 cubic feet of air is necessary 

w 

for complete combusiton of 1 pound of pure carbon, with no air 
excess (theoretical volume required), the volume of air being figured 
for the standard conditions of a temperature of 0°C. and a pressure of 
760 mm. If allowance be made for the average proportions of 
moisture and ash in ordinary coal and coke, the volumes of flue gases 
per pound of fuel become as follows: Cokp 12S cubic feet, anthracite 
coal 120 cubic feet, bituminous coal 123 cubic feet. Lewes 0 gives 
for petroleum 172.9 cubic feet, and Carpenter and Diederichs 6 give 
182.1 cubic feet. If the average, 177.5, be taken, and if the weight 
of a gallon of oil be considered as 71 pounds, 1 gallon of oil would 
take nearly 1,300 cubic feet. 

Gill c gives the volume of air theoretically needed tor the combus¬ 
tion of 1 cubic foot of natural gas as 9.8 cubic feet; of city gas as 
5.Go cubic feet, and of producer gas as 1.25 cubic feet. 

Carpenter and Diederichs d state that 9 cubic feet of air is needed 
for natural gas; 5.25 cubic feet for city gas, and 1 to 1.15 cubic feet 
for producer gas/ 

If the averages for natural and city gas, and Gill’s figure for pro¬ 
ducer gas be taken, the figures are as follows: For natural gas, 9.4 
cubic feet; for city gas, 5.45 cubic feet, and for producer gas 1.25 
cubic feet. On this basis the volume of flue gases from the various 
fuels may be approximately computed. 

For coke, the combustible part of which is practically all fixed 
carbon, and for anthracite coal, the volatile part of which (say 5 per 
cent) may be neglected as far as change in volume between air supply 
and flue gases goes, there is no noteworthy change in ga. volume 
after combustion, the air and flue gas both being measured at standard 
conditions. 

« Lewes, V. B. f Liquid and gaseous fuels, 1907, p. 322. 

* Carpenter, R. C.,and Diederichs, H., Experimental en-inooring, 1912, p. 8X). 

* C.IU, A. IL, Oas-fuel analyses for engineers, 1912, p. 70. 

* Carpenter, R. C., and Diederichs, IL, loo. eit. 

* The figures for producer gas are on richer gas than that represented in Reply 164, used for brass melting. 




FACTORS AFFECTING OPERATION OF BRASS FURNACES. 137 

With bituminous coal there will be a slight increase in volume due 
to the presence of hydrocarbons, which may be figured at about 

3 per cent, making the volume of flue gases about 127 cubic feet per 
pound of soft coal. 

From figures given by Carpenter and Diederichs 0 the volume of the 
products of combustion from 1 gallon of oil would be about 1,400 
cubic feet. 

On natural gas, chiefly CII 4 , the equation involved is— 

CH 4 +20 2 =C0 2 -f2H 2 0 

or the volume of the products of combustion is equal to that of gas 
plus air, or 10.4 cubic feet per cubic foot of natural gas. 

On city gas of average composition, 1 cubic foot will correspond to 
about 6.3 cubic feet of flue gas. 

On producer gas, owing to the diminution of volume in burning 
CO and II 2 , 1 cubic foot corresponds to about 1.9 cubic feet of flue "as 
If, to get the relative order of the volumes of flue gases from different 
fuels, it be assumed that the combustion is both complete and without 
air excess, the figures are as follows: 

Cubic feet. 


Coke, flue gases per pound. 128 

Anthracite coal, flue gases per pound. 120 

Bituminous coal, flue gases per pound. 127 

Fuel oil, flue gases per gallon. 1 , 400 

Natural gas, flue gases per cubic foot. 10. 4 

City gas, flue gases per cubic foot. 6. 3 

Producer gas, flue gases per cubic foot. 1. 9 


From the data presented in the large table and in figure 20, it may 
be assumed that for the fuels represented fairly good fuel consump¬ 
tion per hundredweight of metal in the size of furnaces most used 
is as shown in the tabulation following: 

Fuel-consumption figures for common fuels, per hundredweight of metal melted. 


Kind of furnace: 

Natural-draft, pit, coke.pounds.. 45 

Natural-draft, anthracite.do_38 

Tilting, forced-draft, coke.do_25 

Crucible, oil.gallons.. 2. 75 

Pit, tilting-crucible, oil.do_ 2. 4 

Open-flame, oil &.do_ 2.3 

Reverberatory, oil.do_ 1.2 


On soft-coal, reverberatory, and the various gas furnaces, the data 
are not sufficiently abundant nor concordant to allow fixing an average 
for good practice. Figures for the best, the poorest, and the average 
practice of all replies received are presented in the following table: 


a Carpenter, R. C., and Diederichs, II., loc. cit. 


& With 500-pound charge. 


















138 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


J>\iel-consum pt ion figures on soft coal (per hundredweight), reverberatory and various gat 

furnaces. 


Kind of furnace. 


Kind of practice. 

Reverbera¬ 
tory, soft- 
coal. 

Natural- 
gas, open- 
flame. 

Natural- 

M 

crucible. 

City-gas, 

crucible. 

Producer- 

fa*. 

crucible. 

Heat.... 

Pound 4 . 

1' 

53 

88 

Cu.ft. 

200 

202 

341 

Cu.ft. 

231 

315 

480 

Cu.ft. 

256 

■122 

*50 

Cu.ft. 

J a 3,500 

A verage ... . 

Poorest. 



a Only one report. 


Calculated from the above, the volume of Hue gases from each fur¬ 
nace under standard of 0° C, and 700 mm. pressure conditions, per 
hundredweight of metal melted is shown in the following tabulation: 

Approximate volume of Jlue gases from different types of coal, coke, oil, and gas furnace* 


per hundredweight of metal melted ° 

Kind of furnace: • Feet. 

Pit, natural-draft, coke. 5,800 

Pit, natural-draft, anthracite. 4,550 

Tilting, forced-draft, coke. 3,200 

Pit, crucible, oil. 3,800 

Tilting, crucible, oil. 3,500 

Open-flame, oil. 3,350 

Reverberatory, oil. 1,700 

Reverberatory soft-coal (best). 2,300 

Reverberator}*, soft-coal (average). 6,950 

Reverberatory, soft coal (poorest, on red brass). 11,000 

Open-flame, natural gas best). 2,000 

Open-flame, natural gas (average). 2,900 

Open-flame, natural gas (poorest). 3,500 

Crucible, natural gas (best). 2,300 

Crucible, natural gas (average). i... 3,000 

Crucible, natural gas (poorest). 4, 700 

Crucible, city gas (best). 1,550 

Crucible, city gas (average). 2,400 

Crucible, city gas (poorest).... 4,000 

Crucible, producer gas. 6,200 


As these figures are for the cold gases, the flue gases at furnace 
temperature will be expanded to much larger volumes, but those 
from the different fuels will still be in the ratio given. 

If the effect of any small amount of unburned hydrocarbons be 
disregarded, the volume of flue gases will be greater than that com¬ 
puted if combustion is not complete, so that much CO is obtained, as 
one volume of oxygen used in combustion gives twice as much CO 
as C0 2 . If an excess of air be used, the volume of the flue gases will 
of course be greater than that computed. 


a In computing the volumes of flue gases from gaseous fuels, the figures for gas consumption reported have 
been iiwumed to l*e at the commercial standard conditions of 60* F. and 30 inches of mercury, and have 
been reduced to 0* C. and 760 mm. of mercury. 











































FACTORS AFFECTING OPERATION OF BRASS FURNACES. 


139 


If the discordant data be disregarded for the reverberatory soft* 
coal furnace, it will be seen that coke or coal in natural-draft furnaces, 
under theoretical conditions of complete combustion and no air 
excess, involve the passage of more Hue gases out of the furnace 
than any other fuel except producer gas; and that the forced-draft 
coke, and the oil, natural-gas, and city-gas furnaces have a consider¬ 
able advantage on this point—an advantage, however, that is balanced 
or overbalanced by the greater velocity of the flue gases. 

Inasmuch as producer gas has the disadvantages of possessing a 
low heating value and of giving a large volume of flue gas, it would 
appear that, although the gas is a cheap and suitable fuel for melting 
in crucible furnaces red brass, bronze, or other alloys low in zinc, in 
high-zinc alloys, such as yellow brass, in which the tendency of the zinc 
to volatilize is great, the probability of a high zinc loss in melting is 
great. In crucible furnaces, tightly covered, producer gas might per¬ 
haps be suitable for melting yellow brass, but it should seemingly be 
the last fuel to be used for open-flame or reverberatory melting if a 
low zinc loss is required, although it would be one ef the cheapest of 
fuels if cost of fuel only were considered. 

It should be noted that in the discordant figures on the soft-coal 
reverberatory, the poorest figure reported was one on red brass, 
whereas the rest were on yellow brass or manganese bronze, so that in 
considering the flue-gas volume in regard to zinc loss, this high 
figure can hardly be regarded as typical. 

As the best figure on city gas was reported by a gas company 
instead of directly by a foundry, it will be best to consider the 
average and poorest figures as more typical for that fuel. 

In comparing oil and the various gaseous fuels in regard to zinc 
loss, it must be remembered that the volume of flue gases is pnly one 
of several factors. 

In open-flame furnaces, Reardon a gives the results of a compara¬ 
tive test of oil and natural gas in open-flame furnaces on metal con¬ 
taining 18 per cent of zinc. The quantity of metal melted in each 
test was 4,550 pounds. The consumption of natural gas was only 
143.5 cubic feet per hundredweight, whereas the oil consumption 
was 2.37 gallons per hundredweight—results that would amount to 
only 1,490 cubic feet of flue gases for natural gas as against 3,320 
cubic feet for oil. The loss of metal with natural gas was, however, 
2.69 per cent in comparison with 1.13 per cent with oil. 

1 Iowever, with the gas-fired furnace, 9 hours 54 minutes was required 
to melt 4,550 pounds, whereas with the oil furnace the same quantity 
was melted in 5 hours 52 minutes, the time with gas being one and 
two-thirds greater than with oil. Reply 104 b states that natural gas 

« Reardon, W. J., The manufacture of high-copper castings: Meta. Ind., vol. 8, 1910, p. 212. 
b See p. 98. 




140 BRABS-FURNACE PRACTICE IN' THE UNITED STATES. 


has boon discardo<l in favor of oil in open-flame furnaces in another 
foundry molting metal of about the same composition as was used in 
the tost reported. 

The reason for the greater speed of the oil furnace and its conse¬ 
quent lower molting loss is that oil is what might be called a more 
concentrated fuel than even natural gas; that is, with a suitable 
burner it is possible to burn the oil with a short enough flame to 
confine the combustion inside the furnace and yet to develop enough 
heat to melt a charge of metal in a shorter time than will be taken by 
natural gas to develop the same heat. 

In other foundries, the one represented by reply 15 for instance, 
situated in natural-gas regions, where natural gas is regularly used 
in crucible furnaces, oil is regularly used in the open-flame furnaces. 
Reply 31 gives data on both open-flame, oil, and natural-gas furnaces, 
but gas Is used in only one furnace, whereas oil is used in a dozen 
or more. 

As, on account of the speed factor, natural gas proves less satis¬ 
factory in open-flame furnaces than oil, it follows that city gas or 
producer gas will be still less satisfactory, as they are both lower in 
heat units per cubic foot than natural gas, and both give larger 
volumes of flue gases than does natural gas. 

In one foundry visited occasional melts of copper are made in an 
open-flame furnace. It had been found necessary to raise the pres¬ 
sure of the gas by a “booster’’ in order to obtain any satisfactory 
melting speed. Figures on gas consumption and melting loss were 
not available. 

HIGH-PRESSURE GAS. 

Onslow a advocates the use of city gas at a pressure of about 6 
pounds per square inch for melting metal. 

Goodenough 6 states that high-pressure gas, at a main pressure of 
about 15 pounds per square inch, is largely employed in Birmingham, 
England, for melting metal. 

A furnace taking gas at 7 to 12 (average) pounds pressure is now 
on the English market. 0 

Smith d gives the following comparative figures regarding cost of 
melting brass in high-pressure gas furnaces and coke furnaces. 

a Onslow, A. W., Application of high-pressure gas to furnace uses: Jour. Soc. Chem. Ind., vol. 29, 1910, 
P. 395; abstracted in Jour. Inst. Mot., vol. 3,1910, p. 292; High-pressure gas for manufacturing purposes: 
Gas World, vol. 56,1912, p. 822; Chem. Abst., vol. 6,1912, pp. 2515, 3004. 

b Goodenough, F. W., High-pressure gas lighting in Great Britain: Am. Jour. C.as Light., vol. 97, 1912, 
p. 227. 

t Editorial, High-pressure gas furnace: Engineering (London), vol. 94,1913, p. 531. 

d Smith, E. W., Application of high-pressure gas for melting metals: Am. Jour. Gas Light., vol. 96,1911, 
p.»K>9; Abstracted Jour. Soc. Chem. Ind., vol. 30.1911, p. 1455. 



FACTORS AFFECTING OPERATION OF BRASS FURNACES. 141 




Comparative cost per hundredweight of melting brass in high-pressure gas furnaces and 

in coke f urnaces. 


Item. 

Gas 

furnace. 

Coke 

furnace. 

Cost of pots. 

d. 

4 

s. d. 
0 5 

Cost of metal lost. 

10$ 

7* 

1 4$ 
4i 

Cost of fuel lost. 



COVERS AND FLUXES. 

Zinc loss should be considerably diminished by covering the metal 
with either a solid crucible cover or a molten flux. However, the 
solid cover is almost never used, only two firms having been found 
that use it, one melting manganese bronze in pit coke furnaces and 
the other yellow brass in tilting, crucible, oil furnaces. It has been 
stated by Corse a that the use of a crucible cover decreases the speed 
of melting by a quarter to a third. 

A variety of fluxes is used in refining emery grindings or dirty 
borings; 6 those most used in the melting of clean metal are common 
salt, with or without the addition of silica, sand, and broken glass. 
A layer of crushed charcoal is almost invariably used on the surface 
of the metal, whether or not a cover of molten salt or molten glass 
is used. As fine charcoal is readily blown *out of an open-flame 
furnace, large pieces of charcoal, slabs of wood, or crushed coal are 
often used. Jones c recommends a flux consisting of 1 part fluor¬ 
spar to 3 parts of lime, together with some hard coal. Anhydrous 
boric oxide and charcoal form a cover that is described as promising 
by several firms, although such a cover has not so far found wide use. 

It should be remembered that most molten fluxes or covers attack 
the crucible, or the furnace lining in a furnace not using a crucible, 
so that this disadvantage must be balanced against their advantages. 

Although the fluxes are used mainly for the purpose of fluxing the 
metallic oxides, they serve also as a cover, and thus decrease the vola¬ 
tilization of zinc. When a pot of yellow brass covered with the usual 
salt and charcoal is pulled from the furnace ftt proper pouring tem¬ 
perature, it gives off zinc vapor, which burns as it strikes the air, 
forming a thin white fume of zinc oxide. As soon as the pot has been 
skimmed the zinc oxide rolls up in thick clouds. It seems likely that 
the almost universal use of a salt cover in rolling-mill melting, and its 

a Corse, W. M., In discussion, Trans. Am. Inst. Metals, vol. 6,1912, p. 198. 

b Krom, L. J., Fluxes from the viewpoint of the metallurgist: Metal Ind., vol. 8, 1910, p. 203; Sperry, 
E. S., Fluxes as applied to the brass foundry: Trans. Am. Brass Founders’ Assn., vol. 4,1910, p. 6.; I se 
of salt in melting copper alloys: Brass World, vol. 8,1912, p. 6<; Primrose, H. S., A discussion of modern 
brass founding: The Foundry, vol. 40,1912, p. 366; Ott,C. E., The opportunities of a metallurgical chemist; 

Metal Ind., vol. 8,1910, p. 601. 

c Jones, J. L., Answer to question on melting: Metal Ind., vol. 11,1913, p. 437; vol. 12,1914, p. 81. 













142 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


much less common uso in sand-casting shops, may partly account for 
tho generally greater zinc loss from yellow brass in such shops than 
in the rolling mills, because the pouring temperature in the rolling 
mills is as high or higher than that in the plants making sand castings 
of ordinary thickness. 

Bassett," on the other hand, states that the use of chlorides as 
fluxes in melting brass promotes the volatilization of zinc, and cites 
the almost complete dezincification of thin brass sheets (2.5 mm. 
thick) annealed at 650° C. for an hour, with driftwood as fuel. Bas¬ 
sett’s test shows that flue gases containing the vapor of a chloride 
such tvs sodium chloride will aid the volatilization of zinc, but the 
actual conditions of melting under a molten cover are not strictly 
comparable to the conditions in the test cited. In several of the 
plants visited molten covers of salt or glass were used, and the users 
were strongly of the opinion that such covers reduced the zinc loss. 6 

A molten cover should also tend to make oxidation or other chem¬ 
ical action by the flue gases less rapid, and to prevent the occlusion 
or solution of gases. 

GASES ABSORBED IN MELTING METAL. 

The question of the chemical action of various gases and their solu¬ 
tion in the alloys melted is one on which little authoritative informa¬ 
tion is at hand. The gases to be considered are mainly nitrogen, 
carbon dioxide, carbon monoxide, oxygen, sulphur dioxide, and water 
vapor. In the melting of the constituents of an alloy a gas may enter 
into chemical combination with the copper or the other metals in the 
alloy, forming oxides of those metals, or maybe occluded in the alloy. 

Occlusion is most strikingly illustrated in the melting of silver, 
which, at 1020° C., can absorb about twenty times its own volume of 
oxygen, c the solubility increasing with the temperature. On freez¬ 
ing, silver that has absorbed oxygen gives it up, and it is to this char¬ 
acteristic that the well-known “spitting” of silver on freezing is due. 
Platinum and palladium, in the solid state, can occlude a large pro¬ 
portion of hydrogen, the volume occluded decreasing as the tempera¬ 
ture is raised.^ 

As the absorption of gases by a molten metal is a matter of solution 
rather than of occlusion,* * an increase in temperature increases the 
gas absorption. As the metal freezes, the dissolved gases are liberated. 
If it freezes so rapidly that the gas bubbles can not pass lip through 

a Rassett, W. H., Zinc losses: Jour. Ind. Eng. Chem., vol. 4,1912, p. 164; Metal Ind., vol. 10,1912, p. 239. 

fc See Replies 21, 28,30,91,151 in the large table. 

e Donnan, F. G., and Shaw, T. W. A., Solubility of oxygen in molten silver: Jour. Soc. Them. Ind. 
Vol. 29,1910, p. 987. 

d Findlay, A., The phase rule, 1904, p. 177. 

* However, after the metal has solidified, the gases that are retained are usually said to be occluded. 



FACTORS AFFECTING OPERATION OF BRASS FURNACES. 143 


the metal before it has set, blowholes are formed. Other causes of 
blowholes are the ‘presence of air, x t rapped in pouring, and of gases 
evolved by the mold or cores when the hot metal strikes them, but 
dissolved gas is unquestionably one of the main causes of porosity 
and of blowholes. 

Shepherd and Upton ° discuss this matter as follows: 

A casting trouble that no variation of mold can rectify is the pinholing, or sponginess, 
which is clue to gases occluded in the molten metal. Molten copper and molten 
bronzes down to 85 per cent copper have the power of absorbing gases. When freez¬ 
ing begins these gases are set free, with the result that the mass of the casting is fdled 
with tiny bubbles of sizes from a pinpoint to a pinhead. The only way to avoid this 
is by proper treatment of the melt in the furnace. The absorption of gases is roughly 
proportional to the time the metal is held molten. Hence the furnace was run hot 
and the time of melting kept as short as possible. The metal must be gotten hot, for 
if poured too cold it is practically certain to trap air bubbles. It was found also that 
the occluded gas was much worse in the top of the melt. 

Sperry b says: 

Blowholes in sand castings almost entirely come from the gases generated by the 
combustion of the fuel during the melting and becoming absorbed during the melting. 
As the metal cools in the mold, these gases are expelled, forming blowholes. Blow¬ 
holes and pinholes are the same and are produced by gas absorption. One is simply 
larger than the other. 

The reason why, with the same manner of melting and the same metal, blowholes 
will be present in one casting and not in another is in the method of melting. All 
fuels used in the brass foundry at the present time contain sulphur, and, of course, 
various gases, such as carbon monoxide, carbon dioxide, hydrogen, are generated by 
the combustion of the fuel. It is the sulphur that is a very common cause of the 
trouble, although the other gases play an important part. When the metal melts, it 
absorbs these gases, and then, after it has been cast in the sand mold, they are expelled, 
and blowholes form. 

In melting, therefore, the metal should be protected against these gases. A common 
and excellent method is to keep the surface of the metal covered with charcoal. 

Sperry also states c that slow melting favors the absorption of 
gas and the formation of oxide, whereas too rapid melting overheats 
the projecting edges of the ingots, excessive overheating of solid metal 
causing gas absorption and the formation of blowholes in the castings. 

Carpenter and Edwards d state that one main cause of porosity 
and blowholes is that “when melted, the alloy dissolves gas, the 
amount increasing with the rise of the temperature and the duration 
of melting. The composition (of the gas) depends on the fuel used 
and the way it is applied. But no alloy melted under practical 
conditions escapes contamination by gas.” 


« Shepherd, E. S., and Upton, G. B., The tensile strength of the copper-tin alloys: Jour. Phys. Chem., 
vol. 9, 1905, p. 453. 

b Sperry, E. S., Blowholes in valve eastings: Brass World, vol. 9, 1913, p. 51. 

c Sperry, E. S., Speed of melting of copper and brass: Brass World, vol. 4, 1908, p. 253; Chem. Abs., 
vol. 2, 1908, p. 2926. 

d Carpenter, II. C. II., and Edwards, C. A., Production of castings to withstand high pressures: Engineer¬ 
ing (London), voL 90, 1910, p. 871. 



144 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


Johnson a discusses this feature ns follows: 

The regulation of the quantity of oxygen in copper i» the keynote of all copj**r 
refining. It ia the presence of a well-defined proportion of oxygen in the form of 
cuprous oxide, forming a copper-cuprous oxide eutectic, which enables copper to 
be east free from blowholes. It seems that when oxygen in present, other gaaen are 
leas soluble in molten copper; when oxygen is absent, or is present in insufficient 
quantity, the copper dissolves other gases, such as hydrogen and carbon monoxide, 
which are insoluble in the copper when solid, and, being rejected during the process 
of solidification, cause internal ]>oroeity and external ridges or excrescences. 

Johnson 6 advances the theory that “set” copper—copper with an 
excess of cuprous oxide, an ingot of which freezes with a concave 
upper surface—contains no gas; that “tough-pitch” copper—that 
containing a little oxide, which sets with a level surface—contains 
just enough gas so that the buoyant tendency of the gas in minute 
cavities ju^t counteracts the natural tendency of the ingot to “pipe” 
or set with a concave surface, anti that in “over-pitch” copper— 
copper containing little or no oxide, which freezes with a concave 
surface—there Is enough gas so that the buoyant tendency of the 
gas overbalances the tendency to “ pipe.” He states that a fractured 
surface of “set” copper is entirely free from gas cavities; that a 
fractured surface of “tough-pitch” metal contains minute gas cavi¬ 
ties, uniform in size and distribution, but so small that they do not 
materially affect the mechanical properties of the metal, as they are 
welded together in rolling; ami that in the case of “over-pitch” metal 
the gas cavities are more numerous, larger, and more variable in size 
than in the case of “tough-pitch” metal, the larger cavities occurring 
at the top of the ingot. 

Shepherd and Upton c state that their worst trouble from gas 
inclusions in the copper-tin alloys was with compositions containing 
more than 90 per cent of copper, and that bronzes, with less than 85 
per cent of copper, do not appear to dissolve, or if dissolved, to retain 
gases. 

Lohr d had his worst trouble from gas inclusions in copper-zinc 
alloys with copper percentages of from 65 to 80 per cent, little trouble 
being experienced with a percentage above 80 per cent. He had more 
trouble when illuminating gas was led over the melt than when a 
cover of charcoal and molten salt was used. 

Curry and Woods * * passed illuminating gas over the melt when 
working with the copper-aluminum alloys, an arrangement that they 
found effective in excluding oxygen, so that they had little trouble 
from included gas. 

o Johnson, F., Effect of silver, bismuth, and aluminum upon the mechanical properties of “Tough-pitch” 
Copper containing arsenic: Jour. Inst. Metals, vol. 4, 1910, p. 163. 

If Johnson, F., op. cit., p. 206. 

« Shepherd, E. 8., and Upton, O. B., op. cit., p. 454. 

* Ix>hr, J. M., The tensile strength of the copper-iinc alloys: Jour. Phys. ( hem., vol. 17,1913, p. 20. 

• Curry, B. E., and Woods, 8. H., The tensile strengths of the copper-aluminum alloys: Jour. Phys. 

Chcm., vol. 11, 1907, p. 464. 





FACTORS AFFECTING OPERATION OF BRASS FURNACES. 145 


Primrose a says: 

I he time of a melt should be kept as short as possible, as prolonged “stewing” 
only tends to increase the absorption of gas, which caused blowholes when the metal 
solidifies. 

Weintraub says: 5 

The cause of the difficulty of producing sound, pure-copper castings has been suffi¬ 
ciently well understood for a long time. Molten copper has the property of dissolving 
gases and of setting a part of these gases free on cooling. This produces pinholes and 
even big cavities. The casting obtained is therefore mechanically unsound and has 
naturally a low electrical conductivity. 

The elimination of these dissolved gases presents but little difficulty. It is suffi¬ 
cient to add one of the well-known deoxidizers, such as zinc, magnesium, phosphorus, 
etc., in small quantities to bind the oxygen or the gaseous oxygen compound chem¬ 
ically. The electrical conductivity of the copper thus produced is, however, as a 
rule, low. The amount of the gaseous oxygen compound dissolved in copper during 
the process of melting is a variable quantity and is distributed throughout the whole 
mass. 

Guillemin and Delachanal c state that brasses contain from 1 to 30 
times their own volume of gases, which consist of II 2 , C0 2 , and CO, 
much of the gases being H 2 . These gases were given up only when the 
alloys w r ere heated to the melting point under reduced pressure. In 
pieces not showing blowholes the gas was mainly H 2 , whereas in 
those that did contain blowholes, the II 2 was accompanied by CO 
and a little C0 2 . The II 2 did not seem to injure the physical prop¬ 
erties of the pieces not showing blowholes. 

Guichard d finds, however, that the gas retained by commercial 
copper is mainly C0 2 . 

Reply 203 states that the gases retained by bronze are mainly 
nitrogen. 

Reply 1S9 states that the writer has found C0 2 and S0 3 retained in 
copper and gun metal, but no sulphide sulphur, and that there is no 
trouble in yellow brass from the taking up of S0 2 . 

Reply 173 states that in melting yellow brass in a soft-coal rever¬ 
beratory no troublo has been met from the sulphur in the coal. 

Reply ISO, on a similar furnace, says that no trouble has been met 
from this cause either in manganese bronze or gun metal. 

Sperry e states that sulphur in copper causes blowdioles, referring 
to sulphur present in the copper, not to S0 2 from the fuel, although 
he ascribes blowholes to the presence of S0 2 also. 


a Primrose, II. S., A discussion of modern brass founding: Foundry, vol. 40,1912, p. 366. 
t> Weintraub, E., Cast copper of high electrical conductivity: Trans. Am. Electrochem. Soc., vol. 17, 
1910, p. 207. 

e Guillemin, G., and Delachanal, II., Occlusion of gases contained in certain copper alloys: Metal Ind., 
vol. 9, 1911, p. 36; Compt. Rend., vol. 151,1910, p. 881; abstracted in Jour. Inst. Metals, vol. 4,1910, p. 311. 

d Guichard, M., Sur 1’extraction des gaz du cuivre par la chaleur: Bull. Soc. chem., 4th scr., vol. 11, 
1912, p. 50; abstracted in Jour. Inst. Metals, vol. 7,1912, p. 284. 

e Sperry, E. S., The ellect of sulphur in copper: Brass World, vol. 9,1913, pp. 52, 57. See also editorial, 
Sulphur in alloys: Foundry, vol. 42, 1914, p. 74. 

44712°—Bull. 73—16-10 



14G 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


On tho other hand, the chemist of a well-known firm manufacturing 
valves stated that in his experience some Japanese copper lnul con¬ 
tained considerable sulphur, and that its only cfTect was to give the 
castings a dark color, without altering the physical properties of the 
alloy or giving any foundry troubles. 

Sioverts a finds that N a , C0 2 , and CO are not appreciably dissolved 
by copper, but that S0 2 is rather soluble in it, 100 grams dissolving 
about 0.5 gram of S0 2 at 1,200° C., 0.7 gram at 1,300° C., and 0.95 
gram at 1,500° C., the S0 2 being pure and under a pressure of 1 
atmosphere. 

IIo states also that besides the solution there is some chemical 
action, the equation Cu 2 S4* *2Cu 2 0 = S0 2 + 6Cu being reversible. 

Hoffman, Ilayden, and Hallowell b also state that Cu 2 0, Cu 2 S, 
and S0 2 can bo present together in 11 tough-pitch ’’ copper. These 
authors quote IIampe, c who found that S0 2 , II 2 , and CO were dis¬ 
solved by copper, and that C0 2 was not soluble. lie was able to 
drive out tho other gases by heating in C0 2 . 

They also quote Stalil as finding that 0.025 per cent of lead added 
to copper greatly decreased its ability to absorb gases and made 
copper tough enough to stand hammering, rolling, and drawing, 
although without tho lead the copper was porous and would not 
stand mechanical work. 

Ileyn and Bauer d state that tho reaction Cu 2 S -f 2Cu 2 0 = 6Cu 4- S0 2 
is reversible, stating that under conditions such that the Cu 2 0 can 
exist tho reaction at 900° to 1,100° C. goes to tho right; that is, the 
copper is not attacked by S0 2 ; but that if conditions are such that 
tho Cu 2 0 is not formed or is oxidized (as by charcoal) as fast as 
formed, then S0 2 will attack the copper and form tho sulphide. 

Peters e states that in melting and refining cathodo copper in a 
soft-coal reverberatory S0 2 will be absorbed as long as it is being 
evolved in the fire box, and that its influence is diminished by dipping 
the cathodes in milk of lime before tho metal is charged into tho 
furnace. 

Schenck and Ilempelmann^ have studied tho reaction Cu 2 S + 
2Cu 2 0 = 6Cu 4-S0 2 up to 730° C. and give one equilibrium diagram, 
but report no work on molten copper. 

a Sleverts, A., and Krumbhaar, W., Solubility of gases in metals and alloys: Ber. Deutsch. chcm. Gesell., 
vol. 43, 1910, p. 1893; abstracted in Jour. Inst. Metals, vol. 3, 1910, p. 288; Zeitschr. phys. Chem., vol. 82, 
1913, p. 257. See also Stubbs, C. M., Action of sulphur dioxide on copper at high temperatures: Jour. 
Chem. Soc., vol. 103,1913, p. 1445. 

8 Hoflman, II. B., Ilayden, H. O., and Hallowell, It., A study in refining and overpoling electrolytic 
copper: Tians. Am. Inst. Min. Eng., vol. 38,1907, p. 171. 

< Hampe, W., Beitriige zu der Metallurgie des Kupfers: Zeitschr. Berg-IKltten und Salienen-wesen In 
Preusscn., vol. 21,1873, p. 274. 

* lleyn, E., and Bauer, O., Kupfer und Schwefel: Metallurgie, vol. 3,1906, p. 73. 

« Peters, E. O., Practice of copper smelting, 1911, p. 566. 

/Schenck, It., and Ilempelmann, E., Experimentclle und theoretische Studien fiber die Grumllagen 
der Kupferhfittenprozesse: Metall und Erz., vol. 10,1913, p. 283. 




FACTORS AFFECTING OPERATION OF BRASS FURNACES. 147 

IIuser a says that during the oxidizing smelting process Cu absorbs 
cliiefly 0 2 from the furnace gases, but also some SO, and H 2 , whereas 
II 2 , C0 2 , and CO are not dissolved. When the copper solidifies, 
part of the H 2 forms a solid solution and the S and 0 2 separate as 
Cu 2 0 and Cu 2 S. As the metal freezes, solidification starting at the 
walls of the mold, the eutectics formed by Cu 2 0 and Cu and by 
Cu 2 S and Cu are forced to the center, which is thus enriched in Cu 2 0 
and Cu 2 S. These compounds then react, forming Cu and S0 2 , as is 
shown by the rising of the metal, and by the Cu becoming porous. 

Iliiser further states that the S0 2 dissolved in Cu is mechanically 
removed by poling. 

Hof man b says: “The statement of the insolubility of CO in Cu 
will be doubted by copper re fin ers.” 

Clamer c makes the following statement: 

I am firmly of the opinion that many of our failures which we have ascribed to oxy¬ 
gen are, in reality, due to sulphur. I have made some investigations along these 
lines, and have found that in the most careful crucible melting in coke-fired furnaces 
the metal will take up from 0. 02 to 0.05 per cent sulphur. Copper has the greatest 
affinity for sulphur of any of our metals, outside of manganese, and naturally it tends to 
absorb it if brought into contact with sulphur-carrying gases. Sulphur accumulates 
each time the metal is melted, and this accounts for the dark skin on rerun castings, as 
compared with those of first-melt metal. 

The question of the effect of S0 2 in the flue gases is of consequence, 
because if the effect is harmful, the utility of soft coal in reverbera¬ 
tory or semiproducer furnaces, of producer gas not well purified from 
sulphur , d or of fuel oil high in sulphur e would be diminished. 

The evidence is contradictory. However, it is certain, in view of 
the universal practice of using charcoal (which tends to give an at¬ 
mosphere high in CO and low in O,, with, of course, an abundance 
of N 2 directly over metal to be melted) that CO and N 2 stand out as 
the least harmful. As to C0 2 and II 2 the evidence is contradictory. 
Oxygen certainly, and S0 2 possibly, are harmful, both through 
chemical action and through being held in solution by the melt, to 
be subsequently given out to form blowholes as the metal “freezes.” 
That the charcoal cover does not completely keep out gases, even 
oxygen, is shown by the fact that copper melted under charcoal 
needs a deoxidizer, such as silicon, phorphorus, titanium, or boron 
suboxide, in order to free it completely from oxygen. 

Aside from the above-mentioned chemical methods of degasifica- 
tion, which are usually aimed solely at the elimination of oxygen, 


a Iliiser, F., Kupferraffination mit Magnesium: Metall und Erz., vol. 10,1913, p. 479; Met. Chem. Eng., 
vol. 11,1913, p. 518. 

6 Ilofman, II. O., General metallurgy, 1913, p. 20. 

e Clamer, G. II., Electric melting of copper and brass: Trans. Am. Inst. Metals, vol. 6, 1912, p. 130. 
d Fernald, R. II., and Smith, C. D., R<5sumd of producer-gas investigations: Bull. 13, Bureau of Mines, 
1911, p. 27. 

e Allen, I. C., and Jacobs, W. A., Physical and chemical properties of the petroleums of the San Joaquin 
Valley of California: Bull. 19, Bureau of Mines, 1912, pp. 27, 28. 



148 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 

two methods of getting rid of dissolved gases are used. In the 
lirst method® the metal is poured while very hot, so that gas sot 
freo as the metal cools may escape before the metal sets; in the 
second 6 the metal is allowed to cool in the crucible or ladle to the 
lowest possible pouring temperature, thus releasing most of the gas 
before the metal is poured. It would bo better to melt the metal 
without introducing the gas, than to get the gas in and be forced to 
eliminate it. Just which alloys are the most susceptible to gases 
and just what gases are most harmful are still matters of speculation. 

From the foregoing discussion it would appear easier to prevent 
molten metal from absorbing gases in crucible furnaces than in 
open-flame or reverberatory furnaces; and it would appear that 
natural-draft furnaces, with a slow velocity of the gas passing over 
the metal, would probably give less trouble in this connection than 
would forced-draft furnaces, or oil or gas furnaces. In the replies 
represented in the large table, with accompanying notes, the frequent 
mention of poor results with forced-draft, coal or coke, oil or gas, 
and particularly open-flame oil furnaces, shows that such furnaces 
are more likely to give trouble from gas absorption than are the 
natural-draft coal or coke furnaces. On the other hand, the equally 
frequent mention of the successful use of all these types of furnaces 
for melting metal for castings, such as valves, in which any porosity 
is fatal, shows that these furnaces can bo run without bad results 
from gas absorption. 

On visits to plants in the course of the collection of the data herein 
compiled, the w’riter has seen difficult'castings made from metal 
melted in open-flame oil furnaces that were certaiidy as good as could 
have been made in a natural-draft crucible coke or coal furnace. Pure 
cast copper and the aluminum alloys are as difficult to cast without 
porosity as any alloys known, yet in open-flame oil furnaces they 
are melted with absolutely satisfactory results. 

In one plant the author saw castings that w T ere made from an alloy 
of aluminum with 5 to 8 per cent of magnesium—one of the hardest 
compositions to cast without porosity. Blowiioles or porosity will 
usually occur at the junction of the gate and the casting. Yet cast¬ 
ings from this alloy melted in an open-flame oil furnace were abso¬ 
lutely sound at that point. 

However, at the plant mentioned, as at others successfully using 
this type of furnace, every effort was made to run the furnaces 
with a strongly reducing flame. The matter of whether such furnaces 
are run under oxidizing or reducing conditions seems to make most 


« Reardon, W. J., The manufacture of pure-copper coatings: Metal Ind., vol. 8, 1910, p. 5. 

* Carpenter, II. C. II., and Kdwarils, C. A., Production of castings to withstand high pr««urea: Engi¬ 
neering (London), vol. 90,1910, p. 871. 



FACTORS AFFECTING OPERATION OF BRASS FURNACES. 149 

of the difference between unsatisfactory and satisfactory perform¬ 
ance. The writer was interested in noting in one well-run plant 
using both tilting oil-fired crucible furnaces and open-flame oil fur¬ 
naces that the hoods over the open-flame furnaces were thickly 
sooted, showing that a strongly reducing flame was commonly used 
therein, whereas the hoods over the crucible furnaces were only 
slightly sooty, indicating that the flame used in them was not so 
strongly reducing. 

It would appear that the flue gases from a furnace operating with 
a reducing flame are not so soluble in the metal as those from a fur¬ 
nace operating with an oxidizing flame. 

Inasmuch as it is better to use a little more fuel, burning its carbon 
largely to CO instead of to C0 2 , than it is to get a higher fuel efficiency 
through complete combustion, thereby burning the metal and filling 
it with gas and oxides, the aim of combustion in melting brass and 
bronze should be to burn completely the oxygen of the air supplied, 
rather than to bum completely the carbon of the fuel, as such com¬ 
bustion demands an excess of air. Thus, the proper methods of 
burning fuel in brass melting and in boiler practice are sharply 
differentiated. 

Although any of the commercial types of furnaces can be so run 
as to give little or no trouble from dissolved gas, it would seem that, 
in order to make the proper operation of the furnace more “fool¬ 
proof,” a suitable molten cover or flux should be distinctly advan¬ 
tageous in cutting down gas absorption. The use of such a cover 
deserves more attention than is being given it to-day by foundries 
making sand castings, and there is reason to believe that some more 
efficacious cover than molten salt may bo found for rolling-mill 
work. 

SPEED OF MELTING. 

As gas absorption is proportional to the temperature and to the 
time the metal is held at a given (high) temperature, it is essential 
that, to minimize such absorption,' melting be rapid, and that the 
metal be taken from the furnace the instant it has reached the 
desired temperature. 

As loss of zinc is also proportional to the temperature and to the 
length of time the metal is held at a high temperature, rapid melting 
and prompt withdrawal of the metal are vital if the zinc loss is to 
be kept down. 

This statement does not mean that melting two 50-pound heats 
in an hour is necessarily any better than melting one 100-pound heat 
in the same time, but it docs mean that any procedure that reduces 
the time per hundredweight of melt, or increases the weight of metal 


150 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


melted per hour, will tend to reduce the gas absorption and (ho zinc 
loss. 

Fuel efficiency also demands rapid melting, and the rapid with¬ 
drawal of metal from the furnace. Roughly speaking, the first 
heat in the morning, on most furnaces, will require twice the time 
and twice the fuel that the last heat will. If the rate of heating is 
slow and few heats per day are made, the fuel used in heating the 
cold furnace to working temperature holds too great a proportion 
to the total fuel used throughout the day, and makes the fuel cost 
per hundredweight of metal melted higher than in a furnace using 
the same fuel but giving more rapid heating. Similarly, a fuel allow¬ 
ing great melting speed may from this fact alone have a real ad¬ 
vantage over a fuel cheaper on a heahunit basis, but not allowing a 
rapid rate of melting. 

It also follows that tilting or tapping furnaces, which may be 
recharged the moment one heat is taken out, have an advantage 
over pit furnaces, which must either remain empty while the crucible 
is being taken away, the metal poured, and the crucible brought 
back, or else a cool crucible must be used. As allowing the crucible 
to cool very much between heats shortens its life and wastes the 
heat stored in it, the furnace is usually kept vacant till the crucible 
Is brought back. In pit oil or gas furnaces the burner may bo shut 
off or turnod down while the crucible is out, but in pit coal or coke 
furnaces combustion of the fuel goes on whether the crucible is 
there or not. 

Rapid melting means, also, for a given outlay for furnaces and for 
a given floor space, a lower overhead charge per hundredweight of 
metal than slow melting, and means, in general as well, a lower labor 
cost per hundredweight of melt. 

It is thus worth while to consider what factors in the design of a 
furnace for any given fuel, what fuels, and what methods of operation 
make for the most rapid melting. 

It is a general principle of furnace design, which holds good for 
all furnaces, whatever bo the method of heating, that the greater 
the capacity of the furnace the less the loss of heat through radiation 
and conduction in the furnace walls.® 

In this connection it is worthy of note 6 that the size of the rever¬ 
berator}" furnaces for copper smelting has steadily grown from one 
with a hearth area of 8 by 11 feet in 1800 to one with a hearth area 
of 19 by 120 feet in 1911. 

Mathewson c gives the following tablo bearing on the relation of 
hearth area to tonnage: 

° See Stansfield, A., The electric furnace, 1908, p. 35. 

b See Mathewson, E. P., The development of the revcrljerntory furnace for smelting copper ores: Proa. 
8th. Int. Cong. App. Chem., vol. 3, 1912, p. 113. 

* Mathewson, E. P., loc. dt. , 




FACTORS AFFECTING OPERATION OF BRASS FURNACES. 


151 


Relation of hearth area to tonnage produced. 


Ucarth area of furnace. 

Metal 
melted per 
24 hours. 

Cupreous 
material 
per ton of 
coal. 

Feet. 

19 by 50. 

Tons. 

121.74 

190.7 

234.1 
264.9 

267.1 

270.1 

Tons. 

2.75 

3.94 

’ 4.13 

4.31 
4.30 
4.19 

19 by 60. 

19 by 85. 

19 by 102. 

19 by 112. 

19 by 116. 



For a given volume of charge the smaller the area of the furnace 
walls the less the heat loss, other conditions being equal; that is, in 
the case of a crucible furnace a cylindrical furnace will lose less 
heat and will give a better fuel efficiency and a higher melting rate 
than a square one. 

In the case of open-flame furnaces, the theory calls for a better per¬ 
formance from a spherical furnace than from a cylindrical, oval, or 
rectangular one. 

In a crucible furnace, the larger the charge the better the fuel 
efficiency and the speed. Unfortunately, the larger the crucible the 
shorter its life, so that in pit furnaces a point is soon reached when 
the life of the crucible is so short that the crucible cost per hundred¬ 
weight of metal melted becomes so great that it overbalances all 
other advantages of the large furnace. In til ting-crucible furnaces 
much larger sizes may bo economically reached, but even with these 
the condition soon arises that the labor loss and danger from the 
breaking of one big crucible is so great that the risk can not be 
borne. Thus the open-flame and the reverberatory furnaces take 
the lead for economically melting largo charges. 

Again, the heat absorption by the metal, and hence the speed of 
melting, is greater if there is no crucible wall between the metal and 
the source of heat, so that crucible furnaces are again at a disad¬ 
vantage. 

In the open-flame or the reverberatory furnace the larger and 
shallower the hearth the greater the surface exposed per unit of vol¬ 
ume and the shorter the distance through which the heat has to 
travel through the metal to reach all parts of the melt. Unfor¬ 
tunately, the greater the surface per unit volume the greater the loss 
of zinc and the danger of gas absorption or of oxidation, so that this 
factor prevents going to the use of an extremely shallow bath of 
metal. 

In a cruciblo furnace the taller the crucible and the smaller its 
radius the greater the heating surface per unit volume and the 
shorter the path through the metal through which the heat must 
travel from the crucible wall. Thus the tilting-crucible furnace that 















152 


BKA88-FURNA.CE PRACTICE IN T1IK UNITED STATES. 


uses a tall, narrow crucible has a distinct advantage in fuel economy 
and melting speed over the pit furnace that uses a short, fat crucible 
with considerable bilge. 

With external heating, as with crucibles, the sphero, to which pit 
crucibles more nearly approximate than do tilting crucibles, has loss 
heating surface than the more nearly cylindrical tilting crucibles, 
and is therefore less desirable. 

RELATION OF WEIGHT OF CHARGE TO MELTING SPEED. 

The effect of the size of the furnace—that is, of the volume or weight 
of charge—may best bo seen by plotting the data collected to show the 



relation between weight of charge and time per hundredweight of 
metal melted, which is done in figure 3. Operating conditions vary 
so that large individual variations are shown in most cases, but the 
data are sufficiently numerous for the shape of the curve to bo well 
defined. 













































































FACTORS AFFECTING OPERATION OF BRASS FURNACES. 153 


The data in the large tables, with the exception of those presented 
in subdivisions 21, 22, and 23, relating to pit oil furnaces with several 
crucibles in the same pit, have been plotted in figures 3 to 9, to show 
the relation between speed of melting and weight of charge. The 
scale of figure 9 is different from that used in figures 3 to 8. 

Figure 3, covering natural-draft, pit, coke furnaces, shows that 
furnaces with a capacity of 150 to 250 pounds are the most common 
of this type, and that most of the 
square furnaces have a capacity 
of more than 350 pounds. 

Figure 4,covering natural-draft 
pit, anthracite-coal furnaces, 
shows that this type is a rarity in 
sizes having a capacity of more 
than 275 pounds. In the figure, 
the plotting points for square fur¬ 
naces with a capacity of about 200 
pounds, which lie below the curve, 
represent rolling mills melting 
yellow brass, the comparatively 
greater speed being ascribable to 
the lower melting point of the al¬ 
loy and to the fact that the metal 
is more likely to be takenfrom the 
furnace as soon as it is ready in 
rolling-mill practice than in sand- 
foundry practice, because there is 
no waiting for the molds to be 
put up. 

The curves in figures 3 and 4 
are identical; although coke is 
universally admitted to be capa¬ 
ble of faster melting than coal 
under the same conditions in a 
natural-draft furnace, as the fur¬ 
naces are run in practice, there 
appears to be no difference in the 

in both cases. 

Figure 5 shows the speed of the forced-draft, coal or coke furnaces. 

Figure 6 shows the speed of crucible oil furnaces, both pit and 
tilting. The capacity of the sizes mainly used ranges from 150 to 400 
pounds. It will be seen that burners with higli-prcssure air give no 
better melting speed than those with low-pressuro air. 

Figure 7 shows tho speed of crucible gas furnaces. Not enough data 
are available to fix the curvo with certainty. The same curve used 


speed when the average is taken 



WEIGHT OF CHARGE, POUNDS 


Figure 4.—Relation of speed of melting to weight of 
charge in natural-draft, coal furnaces. • round .pit, 
natural-draft coal furnace, melting low-zinc alloy 
(subdivision 7 of large table); ■ square, pit.natural- 
draft coal furnace, melting low-zinc alloy (subdivi¬ 
sion 8); Q round, pit, natural-draft coal furnace, 
melting high-zinc alloy (subdivision 9); □ square, 
pit, natural-draft coal furnace, melting high-zinc 
alloy (subdivision 10). 

















































154 BRASS-FURN AC E PRACTICE IN THE UNITED STATES. 

in figuro 6 for oil furnaces has boon represented, and fits tho data 
fairly well. 

Figure 8, covering tho open-flamo furnaces, shows much less varia¬ 
tion in speed of melting with the weight of charge than in the previous 
cases, and indicates that this type of furnace would be useful in melt¬ 
ing charges smaller than those for w hich it is commonly used. 

Figure 0, covering re¬ 
verberatory furnaces, has 
been drawn to a different 
scalo than that used in fig¬ 
ures 3 to 8, because of the 
largo charges used. 

In Figure 10 the curves 
of averages shown in fig¬ 
ures 3 to 9 have been drawm 
to tho same scale. It is 
seen that on natural-draft 
coal or coko furnaces there 
is a rapid improvement in 
speed as the capacity in¬ 
creases from 150 to 600 
pounds; that the use of 
forced draft improves the 
speed greatly in furnaces 
with a capacity of 200 
pounds up; that crucible 
oil or gas furnaces all 
along average a much bet¬ 
ter speed than natural- 
draft coko or coal fur¬ 
naces, whereas they aro 
more rapid than forced- 
draft coko furnaces with 
capacities up to about 450 
pounds, but that for ca¬ 
pacities greater than 450 
pounds the forced-draft 
coke furnace is more rapid than crucible oil furnaces; and that the 
open-flame and reverberatory furnaces far surpass tho other types 
at all capacities. 

The pit oil furnaces with several crucibles (subdivisions 21, 22, and 
23 of the largo table) aro not represented by curves, because tho figures 
tabulated under “time per hundredweight of metal melted” aro per 
furnace, and not per hundredweight per crucible. In these furnaces 



0 100 200 300 400 500 600 700 

WEIGHT OF CHARGE, POUNDS 


I'lOVRE 5.—Relation of speed of melting to weight of charge in 
forced-draft,coko or coal furnaces. # pit, forced-draft, coke 
furnace (subdivisions 5 and 6 of large table); X pit, forced- 
draft,coal furnace (subdivisions 11 and 12); O tilting, forced- 
draft, coke furnace (subdivisions 13, 14, and 15). 















































































FACTORS AFFECTING OPERATION OF BRASS FURNACES. 155 


olio length of the heat is longer per hundredweight per crucible than 
the average in any of the other types of furnaces; hence, unless they 



Figure 6. —Relation of speed of melting to weight of charge in crucible oil furnaces. # furnace with 
low-pressure air burner, melting low-zinc alloys (subdivisions 16, 17, and 28 of large table); O furnace 
with low-pressure air burner, melting high-zinc alloys (subdivisions 18 and 29); X furnace with high- 
pressure air burner, melting low-zinc alloys (subdivisions 19 and 30); + furnace with high-pressure 
air burner, melting high-zinc alloys (subdivisions 20 and 31). 


u 

| 

u 

0- 

w 


U 

*—< 
H 

U 

S 

fc, 

o 

Q 

w 

w 

Dh 

CO 


oan bo forced faster than is indicated in the replies tabulated in sub¬ 
divisions 21, 22, and 23 of the table they offer no advantages on the 
score of low zinc loss or free¬ 
dom from gas absorption. 

The variation in speed of 
melting of the furnaces rep¬ 
resented by the replies re¬ 
ceived was 6 to G.3 hours 
per hundredweight at one 
extreme, on 50 to 75 pound 
charges in coke and coal fur¬ 
naces, to 0.07 hour per hun¬ 
dredweight on 2,500-pound 
charges in an open-flame oil 
furnace, and 0.02 hour per 
hundredweight on 14,000- 
pound charges in a reverber¬ 
atory oil furnace. 

The method used by the 
firm making reply 103 (sub¬ 
division 1 of the table), of 
leaving a “heel” of molten 
metal in the pot from one 
heat to another, in order 
that the heat may be trans¬ 
mitted from the walls of the crhcible to the solid metal of the next 
charge through metal instead of largely through gas, as is the case, 
until the new charge begins to melt, when no heel is left, has been 



► 




























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1 

1 














1 

1 














1 

1 














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w 



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100 


200 300 400 500 600 

WEIGHT OF CHARGE, POUNDS 


700 


Figure 7. —Relation of speed of melting to weight of charge 
in pit, crucible, gas furnaces. # natural-gas furnace (sub¬ 
divisions 24 and 27); O city-gas furnace (subdivision 25); 
X producer-gas furnace (subdivision 20). The data on 
gas furnaces arc too few to fix the position of the curve. 
The same curve used in figure 6 has been represented. 









































































































150 


BRA6S-FUBNACE PRACTICE IN THE UNITED STATES. 


successfully used in the writer's experience in a somewhat similar 
case on nonferrous alloys other than brass and bronze. Leaving a 
heel of metal increases tho speed of melting, and therefore tho output 
and tho fuel efficiency. 

CRUCIBLE LIFE. 


In furnaces using crucibles the item of crucible cost, that is, cruciblo 
life, is very important. The life of the crucibles has been plotted 
against their size in figures 11, 12, and 13.° A new cruciblo is sup¬ 
posed to hold about 3 pounds of molten metal per maker’s number; 
that is, a new No. 60 cruciblo holds 180 pounds if filled full. The 


1.0 


i.B 


fe= 0 

Figure 8.—Relation of speed of melting to weight of charge in open-flame oil or natural-gas furnaces. 
• open-flame oil furnace, melting low-zinc alloy (subdivision 32 of large table); O open-flame oil fur¬ 
nace melting high-zinc alloy (subdivision 33); X open gas-flame furnace, melting low-zinc alloy (sub¬ 
division 34); + open-flame gas furnace, melting high-zinc alloy (subdivision 35). 


s* 

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WEIGHT OF CHARGE. POUNDS 


usual charge is nearer 2£ times tho maker’s number. If tho cruciblo 
number is not given, tho charge in pounds is divided by 2£ to get tho 
approximate number. This is also done with special forms of cru¬ 
cibles when tho maker’s number does not bear tho above-mentioned 
relation to tho charge. 

In case an average figure is given for the life of several sizes, this 
has been plotted for each size, and where tho limits of the life are given 



Figure 9.—Relation of speed of melting to weight of charge in reverberatory furnaces. O reverberatory 
oil furnace (subdivisions 36 and 37 of large table); X reverberatory soft-coal furnace (subdivisions 38 
and 39). 


the average is taken; that is, if a reply states that Nos. 40, 60, and 80 
crucibles are used and that the life is 20 to 30 heats, 25 heats has 
been the figure used for each of the three sizes in plotting the curves. 

Figure 11 shows the life of crucibles in pit anthracite-coal furnaces; 
figure 12, in pit and tilting coke furnaces; and figure 13, in pit and 
tilting oil furnaces. The most striking point Ls the amazing variation 
in the life of the same size of cruciblo under approximately tho same 


« Theeurves are merely tentative, to express the facts that crucible life decreases with increase in size and 
that the life in tilting furnaces Is longer than inpitfumaces. The curves are approximations to the averages 
reported, but do not necessarily represent the averages for similar foundry conditions. 

















































































FACTORS AFFECTING OPERATION OF BRASS FURNACES. 157 


conditions. The variation is so great that the exact form of the curves 
is not certain. The curves drawn for pit coal and coke furnaces are 
the same. Although Replies 8, 36, and 79 state that the crucible life 
is less in oil than in coal or coke furnaces, Replies 3 and 188 state the 



reverse to bo true, and Replies 14, 75, and 1S6, covering both fuels, 
note no appreciable difference, and the curves indicate that the pit 
oil furnaces average a slightly better crucible life than do pit coal or 
coke furnaces, as would be expected from the fact tha^t the ash and 





















































































































158 BKASS-FURNACE PRACTICE IN THE UNITED STATES. 

clinker in the coal and coke furnaces have a tendency both to slag 
away the fire clay in the crucible and to adhere to it, and they have 
to be knocked off when the crucible Is pulled. 

Gas is claimed to give a longer life than coal or coke in Replies 12 
and 108, but Reply 201 claims the reverse. 

With increase in the size of the crucible the life decreases rather 
rapidly in all furnaces; hence the factor of crucible cost works di¬ 
rectly against increase in size, which has proved to bo beneficial as 
to speed. In pit furnaces the crucible cost, coupled with the trouble 
occasioned when a crucible breaks in the fire, the labor of carrying a 



Figure 11.—Relation of size of crucible to its life, coal furnaces. 0 round, natural-draft furnaces melting 
low-zinc alloys (subdivision 7 of large table); X square, natural-draft furnaces melting low-zinc alloys 
(subdivision 8); O round, natural-draft furnaces melting high-zinc alloys (subdivision 9); □ square, 
natural-draft furnaces melting high-zinc alloys (subdivision 10); A round, forced-draft furnaces melting 
low-zinc alloys (subdivision 11 ); a round, forced-draft furnaces melting high-zinc alloys (subdivision 12 ). 


large crucible to the mold, and the difficulty of pouring from it, pre¬ 
vents increasing the furnace size beyond a capacity of about 400 
pounds, except in rare cases. 

Figures 12 and 13 show what a great increase in life Is obtained by 
using a tilting instead of a pit furnace. Figure 13 also shows that 









































































































FACTORS AFFECTING OPERATION OF BRASS FURNACES. 159 


high-pressure air is rather harder on the crucible than is low-pressure 
air. 1 igures 11 and 12 indicate that it does not appear to make much 
difference in the life of the crucible whether natural or forced draft 
be used in a pit coke or coal furnace. 

















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In general, the alloys high in zinc, and hence of lower melting point, 
allow a longer crucible life than those low in zinc. 

One variable in the life of tho crucible is, of course, the quality of 
the crucible itself, its composition, its uniformity, its firing in the 































































































160 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


kiln, and, in general, everything that happens to it before it leaves 
the maker’s hands. There is undoubtedly a vast variation in the 
quality of crucibles, but it appears that, although one plant will state 
that the crucible made by A is the best and that that made by B i^ 



















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the worst, another plant, working under as nearly the same condi¬ 
tions as are ever found in two different foundries, will call A’s the 
worst and B’s the best. In other words, there seems to be as much 
variation between different lots of crucibles from the same maker 
















































































































































































































FACTORS AFFECTING OPERATION OF BRASS FURNACES. 161 

as there is between those from different makers. One exception only 
need bo noted—in forced-draft, tilting, coke furnaces a number of 
users report consistently better results from an imported crucible 
than they have been able to get from any make manufactured in this 
country. 

The great variation in life in the same type of furnace and on the 
same alloy shows that, aside from the effect of the melting point of 
the alloy, the chief factor in the life of a crucible is not the type of 
furnace so much as it is the treatment it receives by maker and user, 
and the variations in treatment by the user seem to be far greater 
than the difference in quality of the crucibles when they leave the 
maker. 


PROPER TREATMENT OF CRUCIBLES IN TIIE FOUNDRY. 

Although crucibles are free from moisture when removed from the 
kiln, they rapidly absorb it, and many take up 5 per cent of moisture 
during shipment from maker to user. If, instead of eliminating the 
moisture by a gradual annealing, the damp crucible is put directly 
into a hot furnace, or into a cold one and heated too rapidly, the mois¬ 
ture will be changed into steam so rapidly that the steam evolved 
will blow pieces of the crucible off bodily; that is, the crucible will 
u scalp.” 

To prevent this the crucible must be raised from room temperature 
to a temperature somewhat above the boiling point of water very 
gradually, so that the moisture may bo driven off gradually without 
“ scalping” of the crucible. 

There is always an abundance of waste heat that can bo utilized 
for warming the place where the crucibles are stored. A common 
place for crucible storago in foundries using pit furnaces is just back 
of the battery of furnaces. The waste heat may also bo led through a 
special oven, so provided with dampers that the heat may bo grad¬ 
ually admitted for annealing a fresh batch of crucibles. After 
annealing has been finished the oven may bo utilized as a warm 
storeroom. Crucibles are sometimes stored above a core oven, or, in 
a rolling mill, above an annealing furnace, a good practice if the 
oven or furnace is run constantly enough to keep the crucibles dry. 

Most foundrymen are fairly careful about annealing their crucibles, 
but many do not pay enough attention to the tongs used and the way 
the crucibles are handled with them. The greatest damage to cruci¬ 
bles is dono with improper tongs or with tongs improperly handled. 

There are soveral different types of crucible tongs for pit furnaces, 
some of which aro illustrated in fig. 14. No. 1 is a one-prong type, 
mainly used in pit furnaces burning anthracite coal, as in rolling 
mills. The prong comes just below the bilge, bocauso the diffi- 
44712°—Bull. 73—16-11 



162 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


culty of poking tongs clown through the anthracite and its ash is 
greater than through eoko and its ash, so that tongs that come farther 
down the crucible aro a littlo harder to use in coal furnaces. r i ho 
handles are spread, the tongs squeezed into place, and a link slipped 
over them to seat them tightly. A mechanical hoist, operated by 
hand, air, or electricity, is fastened into the hook at the pivot. 

No. 2 is tho spado type. In tho figure this type is shown with 
hooks on the handles for lifting tho pot by hand without mechanical 
hoist. An iron bar is passed through tho hooks and the pot lifted 
by two men, ono on each si do of the furnace. 

No. 3 represents a two-prong tong, ono prong being above and one 
below tho bilge, with trunnions for pouring. On Nos. 1 and 2 the 
tongs aro used merely for lifting the crucible from tho firo and setting 






Figure 14. —Four types of crucible tongs: /, single-prong type; £, spade tong; S and 4, double-prong tongs. 

1, i, and S are of the “pinch" type; 4 Is of the “grab" type. 

it into the pouring shank. With No. 3, tho crucible is held by tho 
tongs during pouring, being carried on a shank of such form that 
the shank may bo held horizontal wliilo tho tongs aro tilted on the 
trunnions; or, a bail may bo attached to tho trunnions and tho tongs 
and crucibles hold by a traveling crane. 

In tho first throo forms tho crucible is pinched tightly in tho tongs 
and tho tongs aro held in place by a link slipped over the handles. 
To put on tho link and get it tight is hot work, as it must bo done 
directly over tho open fire. Hence tho furnaco tender, instead of 
slipping tho link down just tight enough to hold securely, is prone to 
jam it down, oven driving it down with a poker or a skimmer. 

Tho pinching of tho crucible may in this way bo very severe, as 
the hot crucible is soft and leathery and gives somewhat readily. 









































FACTORS AFFECTING OPERATION OF BRASS FURNACES. 163 


It is common to seo crucibles, the mouths of which have been pinched 
into a distinctly oval shape. Every time the crucible is thus strained 
it is weakened and its life greatly shortened. To prevent this exces¬ 
sive pinching of types designated 1, 2, and 3, each of which may be 
termed the “pinch” type, the type designated 4 in the figure, or the 
“grab” type, has been devised. This is intended for use with a 
mechanical hoist and may bo made with one prong or with a spade 
prong if desired. In using the grab typo the tongs are hooked into 
the hoist and lowered into place, the tongs being spread, and gently 
seated in place; the hoist is then slowly started upward, when the 
tongs take hold and the crucible is held by its own weight. 

A toggle joint may be used instead of the chain illustrated, and in 
some cases hooks like those on No. 2 are put on, and the hoist carries 
an equilateral triangle, vertex down, which is hooked into both hooks 
and draws them down by the weight of the crucible. 

For use in oil or gas furnaces the grab typo with a toggle joint 
may be further improved by making the joint with a pair of stop 
lugs so that the tongs can open only far enough to clear easily the 
bilgo of the crucible. 

The handles of the grab typo aro often bent down at right angles 
just abovo the chain, hooks, or toggle joint, so that the tongs may 
be guided into place without getting the hands directly over the open 
furnace. 

Several foundries that use the grab type of tongs testified that 
with that typo they could without question handle crucibles up to 
No. 250, holding about 650 pounds of metal. No instance of a 
crucible having been dropped by such tongs has been reported. 
Every firm using this type was enthusiastic in its favor, and said 
that no other form would be used, as the grab type greatly increased 
the crucible life. The long life in the natural-gas pit furnaces of the 
crucibles of the firm supplying Reply 15 is ascribed largely to the 
use of the grab tongs. This type seems to deserve a much wider use 
than it now has. 

No matter what type of tongs bo used, if they get out of shape 
and do not fit the crucible at all points, excessive strain is put on 
the crucible at the points where they do touch. In the same way, 
the spado and two-prong tongs, having more bearing surface than the 
one-prong, divide the strain more evenly. 

Some foundries have only one size of tongs, and if now and then 
they have to use a larger or smaller crucible than the size ordinarily 
used, they will use tongs that do not fit it at all. This practice is 
fatal to the life of the crucible. 

A crucible grows slightly smaller with use, owing to oxidation and 
woaring away of the surface. One foundry that reports an ex- 


164 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 

oeptional crucible life has three sets of tongs, differing slightly in 
size, which are selected according to the age of the pot. , 

An easy way to keep tongs in proper shape is to have a cast-iron 
form just the size of the cruciblo used. As soon as it is seen that 
the tongs are slightly out of shape, they can be heated and pounded 
back into shape over the iron form. 

Crucible hoists have been patented with which the cruciblo Is raised 
on the block on which it sets, the block being in turn on a pillar which 
is raised up through the bottom of the furnace by air or hydraulic 
pressure, thus doing away with the lifting tongs entirely. There 
would bo considerable difficulty in adapting this device to a coke 
or coal furnace, but it should be practical as applied to oil or gas pit 
furnaces. A shank can bo designed that will take the crucible 
from the block without the use of tongs, one that would need little 
modification being described by Marteil. 0 Such a scheme, aside 
from putting the crucible to less severe usage, would allow the use 
of approximately cylindrical crucibles, such as are often used in 
tilting furnaces, a practice that would give more heating surface per 
unit volume of metal, and hence a faster melting speed and higher 
fuel efficiency. 

A typo of oil or gas furnace recently patented is made with the 
furnace shell hinged so that it can be opened and the crucible taken 
out by the use of a hinged or “scissor’* pouring shank. However, 
the drawbacks to such a plan are many. 

In rolling mills,.the crucibles are usually lifted from the furnaces 
by a rope hoist operated by hand. The metal is poured while the 
cruciblo is still suspended by the hoist, without putting it in a pouring 
shank. The hand-operated rope hoist has been supplanted by 
electric hoists in a few mills, and controversy rages among mill men 
as to which is better, the hand or the electric hoist. The hand hoist 
requires hard muscular exertion on the part of the workmen, but can 
be operated more smoothly than the electric hoist, thus insuring 
steadier pouring and causing less spilling of metal. One progressive 
mill states, however, that it prefers the spilling of a little metal to the 
strenuous objection of the workmen to the hand hoist iff ter once 
having used the electric hoist. 

An oxidizing atmosphere will burn the graphite from the outside 
of the pot and weaken it; hence for long cruciblo life in any furnace, 
especially in oil or gas furnaces, a reducing flame should be main¬ 
tained. If an oxidizing flame is trained directly on the crucible 
the crucible becomes badly scored at that point. As the burners 
requiring low-pressure air and high-pressure oil are more easily 
controlled so as to give a reducing flame, and as they usually give a 


° Marteil, V., AUiages et fonderie dc bronie, 1910, p. 61. 




FACTORS AFFECTING OPERATION OF BRASS FURNACES. 165 

wider cone of flame, as ordinarily operated, they are easier on crucibles 
than the burners using high-pressure air. 

If oil be allowed to spray strongly on a cold crucible before the 
burner is lighted, the oil will soak in, and “scalping” may result when 
the furnace becomes hot. 

Sulphur dioxide from fuels high in sulphur is said to be highly 
deleterious to the crucible. 

Allowing the crucible to remain in the fire longer than is necessary; 
that is, not taking the pot out when the metal is ready, or allowing 
the metal to “soak,” increases the wear on the crucible; hence 
promptness in taking out the metal lengthens the life of the crucible 
and also prevents gas absorption and loss of zinc. The higher the 
temperature to which the metal is raised, the harder the wear on the 
crucible. In foundries in which alloys of several melting points are 
used, crucibles are usually used for part of their full life in melting 
an alloy with the highest melting point, and are then used for alloys 
with lower melting points. Thus a crucible might be used for a 
couple of heats of pure copper, then for phosphor bronze, then for 
rod brass, next for yellow brass, and finally, for aluminum. Used 
in this way, the total tonnage melted per crucible would probably 
be larger than if each crucible should be used for its full life on one 
alloy. Between changes in the alloy melted, it is necessary to clean 
the crucibles well from any adhering metal to avoid contamination 
from the previous charge. 

Another way in which crucibles are injured is by wedging them 
full of cold ingots or scrap, which expand as they are heated to 
the melting point; the crucible does not expand so much, so that 
a great strain may be set up and the crucible be cracked, or at least, 
weakened. 

Crucibles may also be badly injured mechanically by carelessness 
in poking the fire or in knocking ofi slag and clinkers . 0 

Protective coatings are sometimes used in an attempt to prolong 
the life of the crucible. Ilavard 6 mentions a paint of finely pul¬ 
verized carborundum fire sand mixed with water glass or boric acid, 
and states that there is no doubt but that for certain purposes such 
coatings increase the crucible life. A protective coating of a nature 
somewhat similar to the above is said to be largely used abroad and 
has recently been put on sale in this country. Reports from firms 
that are trying this are not based on long enough experience to be 
conclusive, but indicate that a saving may be effected in this way. 

a For articles on prolonging the life of crucibles, see Anon., Use and care of crucibles in foundry practice: 
Met. Chem. Eng., vol. 10, 1912, p. 182; Jour. Inst. Metals, vol. 7, 1912, p. 309; Sperry, E. S., Graphite cru¬ 
cibles, their use and abuse: Brass World, vol. 2, 1906, p. 1; Johnson, D., Crucible tongs: Metal Ind., vol. 
5, 1907, p. 362; Keeping the tongs in shape: Metal Ind., vol. 6, 1908, p. 93; Bartley, J., Effect of crucible 
soaking: Metal Ind., vol. 12, 1914, p. 12. 

I Ilavard, F. T., Refractories and furnaces, 1912, p. 236. 





1G6 BRASS-FURNACE PRACTICE IN TUE UNITED STATES. 


Bartley a states that in a coni or coke furnace with proper fuel 
space for a given sized crucible the uso of either a larger or a smaller 
crucible decreases the crucible life; Bartley nLso brings out the im¬ 
portant point that crucible life is shorter in square furnaces than in 
round ones, owing, no doubt, to the less even heating. 

Wood 6 cites three rolling mills, one of which used G7 pounds of 
coal per hundredweight and got 25 heats for the life of a crucible, 
another 50 pounds of coal per hundredweight and got 33 heats, and 
a third 33 pounds of coal per hundredweight and got 48 heats, all 
with the same make of crucible. 

If a crucible is not allowed to cool down very far, but is kept hot 
continuously, so that thero is less expansion and contraction, its life 
is lengthened. This is one reason for the longer life of crucibles in 
tilting than in pit furnaces. Replies 6 and 170 show the benefits of 
running a crucible continuously without allowing it to cool. Con¬ 
tinuous operation, of brass furnaces for 24 hours a day is of course 
very rare. However, if the crucibles from a pit furnace, before they 
become cool, are promptly put back into the furnace after pouring, 
and if at night, after the last heat has been poured, the empty cru¬ 
cible is put back in the furnace and allow'ed to cool gradually with the 
furnace, the deterioration due to excessive expansion and contraction 
may be minimized. 

FURNACE LININGS AND THEIR LIFE. 

Questions on the material and thickness of furnace linings and on 
the material and shape of the furnace cover were included in the Est 
sent out, but the replies have not been included in the tabulation. 
Most of the replies concerning covers for pit coal or coke furnaces 
stated that either flat, fire-brick covers (the rolling mills using this 
form almost entirely) or dome-shaped, cast-iron covers w r ero used. 
Flat covers of cast steel or manganese steel w T ero, however, highly 
recommended by a few users, and one firm uses a dome-shaped cover 
of malleable iron. 

On most pit oil furnaces the covers are flat and of solid fire brick. 
On tilting-crucible oil furnaces they are similar, but for charging have 
a hole in the center, w’hich may or may not bo covered by a second 
smaller cover. 

If a “feeder” or preheater is used, as on some pit furnaces of all 
types and on tilting oil and coke furnaces, it is usually fitted into a 
fire-brick ring, which serves as a cover to the furnace, the feeder 
itself not being covered. 

No clear relation was found between the thickness of the lining 
and its life or the fuel consumption. On pit, coal, or coke furnaces 


a Bartley, J., Crucible and furnace relationship: Metal Ind., vol. 11, 1913, p. 166. 

t> Wood, R. A., How much coal does it take to melt a pound of metal: Metal Ind., vol. 11,1913, p. K8. 





FACTORS AFFECTING OPERATION OF BRASS FURNACES. 167 

tlio thickness of the lining varies from 3 inches, in rare cases, up to 
9 inches, also in rare cases, the great majority being about 44 inches 
thick. One user of this type uses a 15-incli wall between adjacent 
furnaces of a battery, so that a furnace may be cool enough to allow 
relining even when those on each side are running. 

Pit oil furnaces and forced-draft tilting coke furnaces have, on 
the average, a 5-inch lining. The average thickness of the lining of 
tilting-crucible oil furnaces is about 6 inches, varying from 4 to 10. 
The linings of open-flame oil furnaces of the 500 to 1,500 pounds 
sizes are mainly 5 to 8 inches thick, with an average of 7 inches. 
The very large furnaces of this type have a 12-inch lining. 

Most of the egg-shaped open-flame furnaces are lined with carborun¬ 
dum fire sand. This is also used in pit anthracite-coal furnaces (Reply 
71, subdivision 7 of the table, and Reply N, p. 118) and is used with 
kaolin and broken glass in one pit oil furnace (Reply 3, subdivision 
16). 

A somewhat similar composition which has been recommended® 
is 70 parts carborundum fire sand, 15 parts ground fire clay, 8 parts 
water glass, and 7 parts water. Ground magnesite brick, or high-grade 
fire brick bonded by tar is also recommended, and for patching fur¬ 
nace linings the use of such a mixture of graphite and fire clay as is 
used in the manufacture of crucibles and is obtainable from crucible 
makers is suggested. 

It is stated 6 that the best fire brick for furnace linings is one high 
in alumina; that it should be of a basic character, so that slag will 
not be formed by the ash in contact with it; that it should have a 
smooth surface, so that clinkers will not adhere, and that it should 
have a high melting point. 

Iligh-temperature asbestos cement is used in one open-fiamo oil 
furnace (Reply 96, subdivision 32), and in one pit gas furnace (Re¬ 
ply 108, subdivision 25). 

A few replies state that there is an increase in the life of the lining 
if special brick of the kind much used for blast-furnace linings be used 
instead of ordinary brick. At various plants tests of linings for pit 
furnaces, both of special clay and of corundite brick are now in 
progress and the results are reported as very promising. 

Reply 152 states that the life of the lining of a tilting-crucible oil 
furnace has been greatly increased by the use of a plastic fire-brick 
composition which is tamped into place, but that this is not suitable 
for coke or coal furnaoes. 

The great majority of all furnaces, however, are lined with ordinary 
firo brick; if square, ordinary shapes are used; round, circle brick, 


a Anon., Furnace-cover linings: Foundry, vol. 41, 1913, p. 3S6. 
b Editorial answer to question on fire brick: Brass World, vol. 9, 1913, p. 373. 




1G8 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 

largo circular sections, or complete circles are used; other shapes are 
lined with special brick. 

The life reported varies greatly, and is largely increased by frequent 
patching of worn places. The variation is extremely notable in open- 
flame oil furnaces, in which a lining may last from 250 heats to over 
24,000, continuous operation (that is, fewer periods of expansion and 
contraction) and very frequent patching being conducive to long life. 
In general, in the same plant and under approximately equivalent 
conditions, for each of a given type of furnace the number of heats 
does not vary greatly with the size; hence the larger the furnace the 
less the repair cost per hundredweight of metal melted. 

VARIATION IN FUEL CONSUMPTION WITH SIZE OF FURNACE. 

The improvement in fuel efficiency with increase in the size of the 
furnace, other conditions being the same, is strikingly shown by the 
following tabulation compiled foom replies each covering several sizes 
of the same type of furnace. 


Relation of fuel consumption to size offurnace. 


Subdi¬ 
vision 
reference 
to large 
table. 

Reply 

No. 

Ftiel. 

Weight of 
charge. 

Fuel per 
cwt. 

1 

82 

Coke. 

Pounds. 

200 

310 

6 7 5 

120 

180 

140 

400 

060 

1,000 

75 

Pounds. 

00 

45 

33 

85 

57 

43 

33 

30 

25 

G3 

1 

188 

.do. 

2 

74 

.do. 

7 

01 

Coal. 

4 

11 

Coal (forced draft). 

\ 150 

| 100 

( 150 

l a 300 

/ 000 

\ 1,540 

38 

29 

26 

27.5 

Gallons. 

2.3 

32 

67 

Oil (open flame). 



\ r '. •* ... 

2.0 


a Reply 11 states that too wide a fuel space was allowed In the 300-pound furnace. 


Reply 79, subdivision 8, of the large table, shows a decrease in effi¬ 
ciency with increase in size of charge but does not consider this result 
normal. 

Reply 63, subdivision 32, also shows a decrease, but ascribes it to 
the fact that the larger furnace was not charged to as near its capacity 
as the smaller. Claims of furnace makers for all types of furnaces 
show that a distinct increase in fuel efficiency is to be expected with 
increase in size, and this rule holds in general. 

In order to show the general trend of the improvement in fuel effi¬ 
ciency with increase in furnace capacity, as well as the wide variation 
in fuel consumption, on the same type and size of furnace and same 
























FACTORS AFFECTING OPERATION OF BRASS FURNACES. 169 

class of alloy, the curves in figures 15 to 19 have been plotted to show 
the relation of weight of charge to fuel consumption. In all, there is 
indicated a distinct tendency for the efficiency to improve as the size 
increases, but the wide deviations from the curves, which are drawn in 
merely as an attempt to indicate an average, shows the vast effect of 
the variations in foundry conditions and in the operation of the fur¬ 
naces. Figures 18 and 19 have been drawn to a scale different from 
that used in figures 15 to 17. 

A few general conclusions, but merely qualitative ones and already 
generally accepted, might be drawn from the curves, such as that fuel 



Figure 15.—Relation between weight of charge and fuel consumption in natural-draft coke furnaces. 
• round, pit furnace, low-zinc alloys (subdivision 1 of large table); B square, pit furnace, low-zinc alloj^s 
(subdivision 2); O round, pit furnace, high-zinc alloys (subdivision 3); □ square, pit furnace, high-zinc 
alloys (subdivision 4 ). 

efficiency improves with increase in furnace size, and that alloys high 
in zinc take a little less fuel than those low in zinc. 

Figures 15 and 16 show nothing conclusive to prove whether round 
or square coal or coke furnaces are more efficient, and figure 18 shows 
no appreciable difference in the oil consumption with high-pressure 
and with low-pressure air on the burners. The tentative curves have 
been plotted together in figure 20, and if the average curves from the 










































































170 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


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data, reported be taken, it would appear tlmt a given weight of an- 
tluracite coal would melt more metal than the same weight of coke, 
but this conclusion is by no means definitely settled. 

If the trend of the tentative average curves be accepted, it would 
seem also that no appreciable difference in fuel consumption was 
obtained in small pit furnaces between using natural and forced draft. 
There is, however, no question but that the larger sizes of tilting, 

forced-draft c«*ke funiacrs 
are far more efficient in 
fuel consumption than pit 
furnaces using natural draft. 

There is not much differ¬ 
ence between the average 
fuel consumption of crucible 
oil or gas furnaces and that 
of the open-flame or rever¬ 
beratory type in the sizes 
common to both types. 
What advantage there is is 
naturally on the side of the 
open-flame furnace. The 
improvement in fuel effi¬ 
ciency in the oil furnaces 
with increase in size is not 
so marked as in coal or coke 
furnaces, although when the 
huge reverberatories are 
reached the oil consumption 
is very materially lowered. 


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MELTING LOSSES. 

In figure 21 the net melt>- 
weight op charge, pounds big loss, or “shrinkage,” as 

Figure 16.— Relation between weight of charge and fuel it is COmmOIlly termed ill 

consumption in natural-draft coal furnaces. # round, pit foundry lias been l)lot- 

furnace, low-zinc alloys (subdivision 7 of large table); , • a t * ^ 

■ square, pit furnace, low-zinc alloys (subdivision 8); ted against 1110 Z1I1C COn- 

round, pit furnace, higb-zinc alloys (subdivision 9); tent of the alloy melted by 
□ square, pit furnace, high-zinc alloys (subdivision 10). . * ^ 

various furnaces. If the 
net loss was not given in the replies, but the gross loss was, the 
net loss has been assumed as two-tliirds of the gross. The bunch¬ 
ing of points indicating zinc contents of 5 and 35 per cent is 
because the bulk of the rc plies were for either red or yellow brass. 

Under strictly comparable conditions the loss would increase with 
the zinc content. That the figure does not show this relation and 
does not show any one type of furnace to give notably higher or lower 







































































FACTORS AFFECTING OPERATION OF BRASS FURNACES. 171 


loss than liny other, indicates that more depends on the operation of 
any furnace than on the furnace itself. 

It would be a hopeless task to determine from figure 21 which type 
of furnace gives the lowest loss for any given alloy, particularly when 
it is remembered that some of the high losses plotted on high-zinc 
alloys for the open-flame furnaces are from figures supplied by firms 


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WEIGHT OF CHARGE, POUNDS 


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Figure 17 .— Relation between weight of charge and fuel consumption in forced-draft coke or coal fur¬ 
naces. # pit coke furnace (subdivisions 5 and 6 of large table); X pit coal furnace (subdivisions 11 
and 12); Q tilting coke furnace (subdivisions 13, 14, and 15). 


that have given such furnaces only a short trial and then discarded 
them, whereas some of the lowest points for high-zinc alloys in these 
furnaces are from data supplied by firms melting a liugh tonnage of 
these alloys yearly. The figure shows some slight increase in melting 

































































172 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


loss with increase in the zinc content of the alloy, hilt when it Ls re- 
called that the actual tendency toward loss in melting increases in 














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WEIGHT OF CHARGE. POUNDS 


Figure 18.—Relation between weight of charge and fuel consumption in crucible oil furnaces. • low-pres¬ 
sure air burner, low-zinc alloys (subdivisions 16, 17, and 28 of large table); O low'-pressure air burner, 
high-zinc alloys (subdivisions 18 and 19); X high-pressure air burner, low-zinc alloys (subdivisions 19 and 
30); + high-pressure air burner, high-zinc alloys (subdivisions 20 and 31). 


the way shown by the boiling-point curve in figure 2, it is seen tliat 
metal loss is on the whole better controlled on the high-zinc than on 
the low-zinc alloys when their relative volatility is compared. 



Figure 19.—Relation between weight of charge and fuel consumption in open-flame and reverberatory 
oil furnaces. • open-flame oil furnace, low-zinc alloys (subdivision 32 of large table); O open-flame oil fur¬ 
nace high-zinc alloys (subdivision 33); + reverberatory oil furnace, low-zinc alloys (subdivision 36); 
X reverberatory oil furnace, high-zinc alloys (subdivision 37). 

# 

Hence no idea of the relative values of different types of furnaces 
can be formed from the averages of the data taken from so many 





























































































































































































































































































ROUND COMPARED WITH SQUARE PIT COKE FURNACES. 173 


different plants working under different conditions. The general 
conclusion that the differences in the operation of a given furnace on a 
giren alloy show more variation in fuel efficiency and melting loss 
than does the use of different types of furnaces on that alloy is justi¬ 
fied by the data represented in figures 15 to 21. Therefore it is wise 
to place more reliance on the reports of tests of various types of fur¬ 
naces on the same alloy and under the same working conditions in the 
plant than on the averages of the data reported. 

Some of the features that are better brought out by the comments 
of the firms replying than by the averages of the data are discussed 
below. 



Figure 20. —Curves showing averages of data as to relation of weight of charge to fuel consumption in five 
types of furnaces. The curves do not necessarily represent the relative behavior of the different furnaces 
under strictly comparable conditions. 


HOUND COMPARED WITH SQUARE, PIT, COAL, OR COKE 

FURNACES. 

Square, pit, coal or coke furnaces are used almost exclusively in 
rolling-mill practice, but rarely in ordinary foundries if the furnaces 
take a crucible smaller than No. 125. Above that size the square 
furnaces are the more common. 

It is said that it is easier and cheaper to reline a square furnace than 
a round one, but with the present prices of circle brick or of complete 
circular sections this advantage can not be great. Another reason 
given is that it is easier to poke the fire in the corners of the square 
furnace. 


































































































































174 BRA88-FUBNACE PRACTICE IN THE UNITED STATES. 


Most of tho users of squaro furnaces outside of the rolling-mill 
operators admit that fuel efficiency would bo better in a round fur¬ 
nace. Tho main reason usually given for tho uso of tho largo squaro 
furnaces is that it is not possible to get the tongs down over the bilgo 




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1 10 12 14 16 18 20 22 24 26 28 30 32 34 36 u 

ZINC IN ALLOY. PER CENT ovel 

ting loss to rinc content of alloy melted: • natural-draft coke furnace; Onatural-draft coal fuma 
furnace; A crucible gas or oil furnace, low-pressure air burner; £ crucible gasor oil furnace, high-press; 
• gas or reverberatory oil or coal furnace. 




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of the crucible in round furnaces without allowing too great a fuel 
space, whereas in square furnaces the corners allow the tongs to go 
down easily. Data in this connection are tabulated below, the data 
being selncted from the large table. 














































































































































































































































ROUND COMPARED WITH SQUARE PIT COKE FURNACES. 175 


Data on round as compared with square , pit , coal or coice furnaces. 

ROUND FURNACES. 


Roply No. 

Subdi¬ 

vision 

No. 

Inside 
diameter 
or length 
of side. 

Cruci¬ 
ble No. 

Outside 
diameter 
of cruci¬ 
ble at 
bilge. 

Fuel 

space. 

Alloy 
melted .a 

Fuel 

used. 

Fuel per 
hundred¬ 
weight of 
metal. 

Cruci¬ 
ble life. 



Inches. 


Inches. 

Inches. 



Pounds. 

Heats. 

14. 

1 

27 

250 

17 

5 

R. B_ 

Coke.... 

30 

18 

21. 

9 

21 

200 

16$ 

2? 

Y. B.. 

Coal... 

33 

25 to 35 

24. 

12 

22 

200 

16$ 

21 

Mn. Bz.. 

Coal and 

t> 50 

15 








coke. 



82. 

1 

26 

300 

17$ 

4$ 

R. B_ 

Coke.... 

33 

33 

Average. 





3B 



35.8 

24 











SQUARE FURNACES. 


38. 

2 

24 

300 

174 

70. 

2 

24 

300 

17$ 

74. 

2 

24 

3(40 

17$ 

79. 

8 

22$ 

200 

16$ 

87. 

2 

24 

300 

17$ 

87. 

4 

24 

300 

17$ 

189. 

10 

18 


15J 

201. 

2 

22 

250 

17 

Average. 











33 


G.M... 

Coke.... 


16 

3; 


R. B_ 

.. .do. 

30 to 50 

13 

3 


G.M.. 


25 

25 

4 


R. B_ 

Coal. 

35 

12 

3$ 

R. B_ 

Coke.... 

45 

IS 

3; 


Mn. Bz.. 

.. .do. 

c50 


ll 


Y. B_ 


32 

40 

2 


Fb. Bz.. 

Coke.... 

35 

18 

3H 



37.8 

20 


a In this column R. B. signifies red brass composed approximately of S5 parts copper, 5 parts zinc, 5 parts 
tin. and 5 parts lead; Y. B., yellow brass, approximately 66 parts copper and 34 parts zinc, with or without 
a little lead; Mn. Bz., manganese bronze, approximately 56 parts copper and 41 to 42 parts zinc, with 
some iron, tin, aluminum, and manganese; G. M., Gun metal approximately 88 parts copper, 10 parts tin, 
and 2 parts zinc; Fb. Bz., leaded bearing bronze of, say, 78 parts copper, 7 parts tin, and 15 parts lead. 

5 Forced draft is used part of the time. Furnaces not pusned to lull capacity. 

cMost of the information supplied indicates that manganese bronze or other high zinc alloy required 
less fuel per hundredweight than red brass. Reply 87 is an exception. 


Replies 1S9 and 201 are the only ones in which the square furnaces 
show less space between the bilge of the crucible and the nearest 
point of the furnace wall than the round ones, and the average space 
in the round furnaces is only one sixty-fourth inch less than in the 
square ones. 

The fuel consumption shows no notable difference, though the 
average is in favor of the round furnace. However, Reply 6 states 
that in a forced-draft, tilting, coke furnace alteration from a square to 
a round form (maintaining the same volume of coke space) effected 
a fuel saving of 17 to 20 per cent. 

Reply R states that in rolling-mill work actual experiment showed 
that round furnaces were distinctly moro economical than square. 
The size and standing of the firm supplying this information entitle 
its opinion to great weight. 

Reply 67 indicates the superiority of the round form. 

Reply 79, though from a plant usin*g square furnaces, states that 
round ones require less fuel and give a more even heat. 

Reply 95, from a rolling mill, states that their experience is that 
the square furnaces give a lower fuel consumption. 

















































































176 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 

Kopiy 110, on the other hand, states that round furnaces are better 
than square. 

Sexton ° says that it is obvious that round furnaces are better than 
square, whereas Bartley b says that the crucible life Is better in round 
furnaces. Although the foregoing table is not conclusive on this point, 
the average is again slightly in favor of the round furnaces. 

It would bo worth while to try closing up two opposite corners of 
a square furnace into circular shape if it is felt that the other two 
corners are needed for admitting the tongs, to determine whether the 
fuel efficiency would not bo increased. This arrangement should 
give half the advantage of a completely round furnace over a com¬ 
pletely square one. 

Bartley claims that crucible life is decreased when either too small 
or too largo a crucible is used. This claim seems reasonable, but 
tabulation or plotting of the data received to show the relation 
between crucible life and fuel space does not give conclusive indica¬ 
tion one way or the other. 

RELATION OF COAL OR COKE SPACE TO FUEL EFFICIENCY. 

It is obvious that the use of too largo or too small a crucible in 
a furnaco will decreaso the fuel efficiency. Too largo a crucible 
requires constant additions of cold fuel, chilling the fire as well as 
making a higher labor charge. Too small a crucible results in loss 
of heat between the furnace walls and the crucible. However, it is 
difficult to determine the proper fuel space, and here again tabulating 
or plotting the data received leads to no definite conclusion. It is 
nocessary to fall back on the comments of firms who have performed 
properly regulated experiments. 

Sexton c says that the layer of coke need not bo thick, 3 or 4 inches 
being sufficient. Bartley d says that good foundrymen vary in 
opinion on this point, some preferring a 3-inch space and others a 
space as thick as 6 inches on a No. 60 crucible. Bartley's experi¬ 
ments were on a No. 70 crucible with a 4-inch fuel space. 

A similar difference of opinion was found in talking with managers, 
superintendents, and foremen at the plants visited. The general 
evidence is that 3 inches on Nos. 40 to 100 and 4 inches on larger 
sizes is ample. 

A fuel engineering company states, “In coke firing, the space 
between the crucible and the furnace walls should not be more than 
3 inches for fuel economy/’ • 

There is considerable evidence to show that many furnaces in use 
have too largo a fuel space, as a number of reports state that a larger 

a Sexton, A. II., Alloys, p. 200. 

t> Bartley, J., Crucible and furnace relationship: Metal Ind., voL 11,1913, p. 106. 
c Sexton, A. II., loc. cit. 
d Bartley, J., loc. cit. 



ROUND COMPARED WITH SQUARE PIT COKE FURNACES. 177 

crucible than is commonly employed can be used, with no more coke 
consumption for the larger charge than for the smaller, and that the 
heat takes no longer. The use of a larger crucible consequently means 
an improvement both in fuel consumption and speed of melting per 
hundredweight of metal melted. Examples of this are Reply 33, 
stating that less coke per heat is used in their furnaces for a No. 125 
pot than for a No. 80, and Reply 140, which states that the firm 
represented uses progressively less fuel for a No. 80 and a No. 90 
than for a No. 70. 

Similar evidence is given by Reply 125, which states that when 
the furnace lining is new the fuel consumption is 25 pounds of coke 
per hundredweight, and that when the lining is worn thin, allowing 
greater coke space, 33 pounds is used. Reply 22 attempts to even 
up the average size of the furnace by making it taper slightly toward 
the bottom, thus perhaps having a little less coke space than is ideal 
at the first, and a trifle more near the end of the life of the lining. 

On the whole, it appears that many users of pit coal or coke fur¬ 
naces might find a distinct improvement in fuel economy and speed 
per hundredweight by using a crucible a size or two larger than they 
use ordinarily. 

The height of the bed of fuel upon which the crucible is set in this 
type of furnace is important. One old furnace tender said, in con¬ 
versation during the author’s visit to his plant, that when with a 
thick fuel bed he had used 50 pounds of coke per hundredweight of 
metal on a No. 70 crucible of rod brass, he had shortened the furnace 
(raising the grate bars and keeping the flue in the same position), 
thus obtaining a thinner bed and a fuel consumption of only 254 
pounds per hundredweight. 

IMPORTANCE OF DRAFT IN NATURAL-DRAFT FURNACES. 

Another feature of great importance in natural-draft furnaces is 
the strength of the draft. Few plants have any definite knowledge 
concerning this feature, as not half a dozen of the firms interrogated 
answered the question bearing on it, so that not enough data were 
collected to be of value. Some foundries that have a long row of 
pit furnaces on the same flue have so much variation in the draft 
between those nearest to and farthest from the stack that the nearer 
furnaces will get out a heat two-thirds quicker than will furnaces at 
the end. To remedy this variation, one rolling mill builds separate 
flues to the stack for each set of three furnaces, instead of allowing a 
dozen or more to run on the same flue. Natural-draft furnaces vary 
so much in strength of draft with the wind and with the humidity of 
the air that the length of any one heat is an unknown quantity. In 
general, the better the draft, the higher the fuel efficiency. 

44712°—Bull. 73—16-12 



178 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 

Rolling mills in general use higher stacks than foundries, and tho 
better draft accounts in part for the better fuel efficiency and greater 
melting speed shown by rolling mills in general as compared with 
foundries melting tho same alloys and using tho same fuel. 

The size of the fuel also influences the draft, too small sizes of coal 
or coke, or fuel with both large and small pieces, resulting in the 
filling of tho openings between the large chunks by tho smaller ones, 
impeding tho draft considerably. Tho size and spacing of tho grate 
bars also makes a difference in the strength of the draft. 

FURNACE FUELS. 

COMPARISON OF METALLURGICAL AND BY-PRODUCT COKE. 

The bulk of tho pit coke furnaces uso 72-hour Conncllsville coke; 
48-hour Connellsvillo coko being second, and by-product coke 
finding only small use. At equal prices for hard Connellsville coke 
and for by-product coke at tho foundry door, the hard coke is un¬ 
questionably cheaper. It will melt more metal per ton than the 
by-product coke, and requires less labor, as the by-product coke is 
less dense and burns faster, thus requiring more frequent firing. 

Yet there are many foundries that pay high prices and high freight 
rates for metallurgical coko when by-product coke, obtainable near 
at hand, would bo tho cheaper fuel. The foundryman is accustomed 
to using metallurgical coke in his iron cupola, as there a strong coko 
is needed to support tho charge, and he assumes that because it is 
tho better for iron it must needs be the best for brass, whereas the 
two conditions are not comparable. Such problems must be solved 
by each plant according to the existing conditions. 0 

COMPARISON OF COAL AND COKE. 

Hard coal is used by yellow-brass rolling mills almost to the ex¬ 
clusion of other fuels. The furnaces have not been notably improvod 
in the past hundred years. Whether this fact is mainly due to the 
inherent advantages of the pit coal furnaces or to the natural con¬ 
servatism of an industry that is highly localized and is in tho hands 
of some 60 firms is a question. The furnaces are so proportioned that 
when the coal added at the beginning of tho heat has been burned, 
the heat of metal is usually ready to come out, recoaling being rarely 
needed, resulting in lessened labor cost. 

With alloys having higher melting points, the greater speed of 
melting with coke gives it a decided advantage, so that in ordinary 
foundry work, on red brass, for example, pit coke furnaces far out¬ 
number pit coal furnaces. 


a See Dean, W. II.,Coal vs. by-prodoct coke in the brass foundry: Mctul Ind., vol. 8,1910, p. 461. 




FURNACE FUELS. 


179 


COMPARISON OF FORCED-DRAFT AND NATURAL-DRAFT COAL OR COKE 

FURNACES. 

The users of forced-draft pit coal furnaces are mainly those who 
have found that natural draft would not give them the high tem¬ 
perature needed to pour metal for light work in any reasonable time, 
or who have copied the installations of earlier firms in their locality. 
Yet the advantages of forced draft even for pit furnaces are consider¬ 
able. Although the construction of such a furnace is more expensive, 
and although a blower and power are required for its operation, the 
speed of melting is under vastly more efficient control, and a tall stack 
is not necessary. If the metal is hot enough to be poured, but the 
molds are not ready, the blast can be closed and the metal “held 
back” in a forced-draft furnace with less fuel consumption and less 
metal loss than in natural-draft furnaces, in which combustion is 
less readily retarded, and the temperature of the metal increases as 
long as the pot is in the fire. This advantage, of course, accrues 
also to gas or oil furnaces. 

Tilting coke furnaces, which, of course, must be run under forced 
draft, show a vast increase in melting speed, crucible life, and fuel 
efficiency over pit coke furnaces of the same size. At present fuel 
prices the forced-draft tilting coke furnace probably gives the lowest 
fuel cost per hundredweight of metal melted in most localities, except 
the Pacific coast, of any type of furnace of no larger capacity except 
possibly the natural-gas or producer-gas furnace. Large open-flame 
gas or oil furnaces, even at the present price of fuel oil, and largo re¬ 
verberatory furnaces may, in many localities, still have an advantage 
in fuel cost, besides that of no crucible cost. 

The main objection to tilting, forced-draft, coke furnaces for work 
for which a tilting or tapping furnace might bo used, is that most 
makes are hard on the furnace tender, some users describing them as 
“man-killers.” Unless put in a pit, as is done with one make, con¬ 
siderable lifting in charging and in the frequent coking is required. 
The furnace tender finds the heat around these furnaces greater 
than around almost any other type. Replies 74, 79, 81, and 180 
agree on this feature. 

The melting loss in this type is claimed by many to be excessive. 
For material low in zinc, the loss figures given in the large table (sub¬ 
division 13) for replies 79 and 152, the accuracy of both of which is 
unquestionable, should sufficiently controvert the idea that the fur¬ 
naces can not be run without a high loss. Reply 79 (subdivision 15) 
also shows that in melting yellow brass for work that does not require 
a high temperature, their behavior, if they aro properly handled, may 
be entirely satisfactory. The losses on high-zinc alloys cast at high 
temperatures as noted in the replies listed in subdivision 14 of the table 


180 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


are higher than the loss shown by the best practice for some other 
types of furnace. Yet the figures on yellow brass or manganese 
melted in this furnace are so few that they should bv no means be 

w r 

taken as proving that the zinc loss can not, with careful handling, be 
reduced to such a point that the over-all cost will not be less than that 
in other types if the favorable speed, crucible life, and coke consump¬ 
tion be considered. 

These furnaces are also severely criticized on the score of gas al>- 
sorption by the metal, many foundrymen claiming that it is im¬ 
possible to make from metal melted in them castings that will stand 
pressure. However, one user is making a red-brass casting that must 
stand steam pressure, and be absolutely free from dross on a ma¬ 
chined surface. Another is making a high-grade valve, and still 
another is making yellow-brass plumbing goods, and all are pro¬ 
ducing a high class of product. 

For low-zinc alloys to be poured into heavy' chunky work, like car 
bearings, their value is unquestioned, and even for more difficult 
work a foundryman who desires a high melting speed and is not able 
to get fuel oil at a reasonable price, or with reasonable certainty of 
prompt delivery, would do well to consider carefully the advantages 
of these furnacc-s. 


LIQUID AND GASEOUS FUELS. 

Natural-gas or oil crucible furnaces insure ease of control, cleanli¬ 
ness, freedom from handling fuel or ashes, great melting speed, long 
crucible life 0 when properly designed and operated, and such control 
of combustion as to make possible the maintenance of a reducing 
atmosphere. These advantages place the oil and gas furnaces far 
ahead of natural-draft coal or coke furnaces, except, possibly, when 
yellow brass or manganese bronze is to be melted. 

Brasseur 6 cites tests on the same alloy (composition not given) 
which showed a tensile strength of 17,000 to 21,000 pounds per square 
inch and an elongation of 3 per cent when the alloy was melted in a 
coke-fired furnace, and a tensile strength of 33,000 to 38,000 pounds 
per square inch and an elongation of 13 per cent when the alloy was 
melted in an oil-fired furnace. Such a difference would, however, 
seldom be found. Brasseur gives the comparative melting losses as 
2 per cent with coke and 1J per cent with oil, and claims that this 
saving, as well as improved quality of product and a decreased labor 
cost, far overbalances the slightly increased cost of fuel when oil is 
used. 

« Although shorter crucible life is claimed by many for them than for natural-draft coal or coke furnaces, 
the averages of the data represented In figures 11 to 13 are in their favor. 

* Brasseur. M., L’application duchaulTage al’huile lourde aux fours m< { tallurglqu«?: Rev.de m^t., 
vol 10. 1913, p. 931. 





FURNACE FUELS. 


181 


Although excessive gas absorption in melting all alloys and ex¬ 
cessive zinc loss in melting high-zinc alloys are claimed by their op¬ 
ponents to occur in the use of gas or oil furnaces, the bulk of testi¬ 
mony is that the quality of the metal produced is fully equal to that 
produced in the old-style pit furnace. 

In cases like this, when a number of foundrymen state in good 
faith, but usually on the basis of short experience with oil or gas 
furnaces, that such furnaces can not be run to give as good results 
as the old-style pit furance, and when an equal or greater number, 
with vastly more experience with the newer furnaces, state that they 
can be run to give as good results and that they are daily being so 
run in their own plants, it is necessary to give more weight to the 
testimony of the foundrymen who can and do get good results than 
to the testimony of those who can not. •> 

It must be granted that the speedier furnaces require a wider 
knowledge of combustion and more care on the part of the furnace 
tender. The natural-draft pit coal or coke furnaces have been used 
for a century and more, being a direct outgrowth from the Bronze 
Age and the days of calamine brass, and their operation has become 
well known, whereas the gas and oil furnaces have been in commercial 
use less than a score of years. However, the advantages of the use 
of liquid or gaseous fuel so far outweigh those of solid fuel that what 
they lack of being “fool proof” is more than compensated with the 
possible but by no means certain exception of their use on high-zinc 
alloys. 

NATURAL GAS. 

Of the liquid and gaseous fuels, natural gas, where it is available, 
' deserves first mention as regards cheapness. For use in crucible 
furnaces on low-zinc alloys, natural gas, at the prices current in 
most natural-gas regions, shov r s high over-all economy. One draw¬ 
back is the liability of the pressure in the pipe lines to drop badly 
in cold weather—a feature that has forced some plants to install 
an emergency oil system for use when the gas pressure fails. 

Where oil can be had at a low price the greater speed attainable 
and the consequent decreased loss of zinc by volatilization have 
led most of the users of open-flame furnaces, particularly furnaces 
for alloys high in zinc, to prefer oil for fuel, even though natural 
gas was available. If the gas and air were both preheated it 
might easily be possible to increase the melting speed enough to 
offset the advantages of oil, particularly at the ruling prices. The 
figures reported for fuel consumption on natural-gas furnaces are not 
as good in comparison to other fuels as would be expected from the 
relative performance of natural gas in other lines of industry, so that 
its possibilities are probably greater than the reported results indicate. 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


182 


CITY OA8. 

City gas, on account of its general high price, has so fur found 
little use in brass-inciting furnaces. However, in some localities a 
low price is made for city gas for industrial use. Under such 
circumstances, particularly if the gas pressure be raised and both 
gas and air be preheated, it would approach natural gas in feasibility. 
Suggestion has even been made that brass inciters doing a largo vol¬ 
ume of work might profitably install a small gas plant of their own, 
the lower labor cost at the furnace being considered enough to offset 
the installation and labor charges on the gas plant. 

Another possibility that should be considered is the use of waste 
gas from by-product coke ovens. Such gas averages 500 British 
thermal units per cybic foot,® or SO per cent of the calorific value of 
average city gas, and is said to be giving good service in open-hearth 
steel melting; it should rank between city gas and producer gas as 
regards melting speed and metal losses in brass melting. Becker 
and Robertson state that it is applicable for melting brass, but no 
figures on its operation are available. 

PRODUCER GAS. 

Producer gas, on account of its high nitrogen content and the rela¬ 
tively largo volume of waste gases it produces, seems of doubtful value 
for open-flame or reverberatory furnaces, although its success in 
large-scale reverberatory furnaces for melting iron puts it in a more 
favorable light. Cold producer gas is out of the question, but with 
properly preheated gas and aif, or perhaps the semiproducer type of 
installation, reverberatory furnaces are a distinct possibility for low- 
zinc alloys. 

Hughes b speaks of a producer-gas reverberatory furnace having 
a capacity of 25,000 pounds as the furnace ordinarily used for refin¬ 
ing red brass borings in I^nglisli practice. 

A fairly large installation of furnaces is essential to make the cost 
of installing and running a producer worth while. 

On the whole, the use of producer gas for brass melting is still in 
the experimental stage in this country, although for the conditions 
of the plant furnishing the data in reply 1G4 (subdivision 26 of the 
large table) it has been a successful experiment. 

Bulmahn c discusses fully the application of producer gas in a 
foundry making red-brass castings. 

a Becker, J., and Robertson, L. B., Production and industrial application of by-product coke-oveu 
gases: Jour. Ind. Kng. Chem., vol. 5,1913, p. 491. 

*> Hughes, 0., Nonferrous alloys in railway work: Jour. last. Met. (British), vol. 6,1911, p. 94; Castings, 
vol. 9,1911, p. 13; Metal Ind., vol. 9, 1911, p. 42f>. 

c Bulmahn, E. F., The application of producer gas lo brass foundries: Traas. Ain. last. Metals, vol. 7, 
1913 (not yet published). 





FURNACE FUELS. 


183 


Producer-gas melting, with regenerative heating of gas and air, is 
also being tried in one rolling mill. Pit furnaces are used and the 
crucibles are not covered. The experiments have not yet gone far 
enough to be conclusive, but a fuel consumption of 35 pounds of a 
low-grade soft coal per hundredweight of yellow brass melted has 
been obtained. The coal costs only $2.25 per ton. No actual fig¬ 
ures on melting losses are yet available, but it is stated that a com¬ 
parison of the composition of the material charged with the composi¬ 
tion of the metal obtained shows the loss to be the same as in coal or 
coke furnaces. This residt applies both to yellow brass and to Muntz 
metal.. 

Therefore no gain as to melting loss is expected. That less hand¬ 
ling of fuel is required and that the ash does not have to be treated 
for the recovery of metal are thought to give the use of producer gas 
at least an even chance with the ordinary type of furnaces. The 
metal from the producer-gas furnaces is stated to be of just as good 
quality for rolling as that from coal or coke furnaces. 

A firm making gas producers reports that it attempted to apply 
producer gas to an open-flame brass furnace, but that the attempt 
was a total failure on account of excessive zinc losses. 

For melting yellow brass or manganese bronze, producer gas is 
badly handicapped by its low heating value and high nitrogen con¬ 
tent, so that naturally this experiment and those of the rolling mills 
on its uso in reverberatory furnaces have not so far met with com¬ 
mercial success. 

Waste blast-furnace gases of 00 to 100 British thermal units® are 
available in large volume in certain localities. Blast-furnace gas is 
said b to bo of too low heating power to be useful for open-hearth 
steel melting, but such use is said to be feasible if it be mixed with one- 
third or one-fourth of its volume of waste gas from bv-product coke 
ovens, a waste gas also available in some of the localities in which 
blast-furnace gas can be obtained. Such a mixture should stand 
on an even basis with producer gas, and, inasmuch as its components 
are wastes, should bo cheaper where available. Gouvy c states that 
coke-oven gas is suitable for heating reverberatories, but that blast¬ 
furnace gas is hardly suitable for this purpose, although it is being 
tried in Germany*. 

FUEL OIL. 

Fuel oil is of several varieties, ranging from the heavy California 
and Mexican crudes and the lighter Pennsylvania crudes (the crude 

« Crabtree, F., Cheap power in the Pittsburgh district: Trans. Am. Electrochem. Soc., vol. 17, 1910, p. 
97; Thaler, H., Values of blast-furnace gases: Oest. Zeitschr. f. Berg- u. Hilttenwesen, vol. 61, 1913, p. 71; 
<71601. Abe., vol. 7, 1913, p. 2033. 

b Becker, J., and Robertson, L. B., loc. cit. 

c Oouvy, A., Utilization of blast-furnace and coke-oven gases: Engineering (London), vol. 94, 1913, 
p. 6S4; Jour. Ind. Eng. Chera., vol. 5,1913, p. 255. 




184 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


may or may not be partly freed from sulphur) through “residuum,” 
which is a residue after the light oils, such as gasoline and kerosene, 
have been distilled oir,° to a light product obtained by distillation. 
This is stated * 6 to be giving good results for crucible-stool melting. 
On the other hand, the catalogue of a maker of open-flame furnaces 
cont ains the following statement: 

If the grade of fuel oil known as distillate is used (which may consist of gasoline or 
benzine residues), 4 or 5 gallons may be required to melt 100 pounds of brass—more 
than double tho amount usually used. The loss from volatilization with such an oil 
is high, and on account of its low gravity the weight per gallon is less than with an oil 
of higher gravity. 

Sherman and Kropff c lind that, although the calorific value per 
pound decreases as tho specific gravity increases (or as tho degrees 
Baum6 docreaso), tho variation in density more than compensates 
for the increase, so that the heavier the oil tho higher the calorific 
value per gallon. 

Tho oils covered by reports of firms replying to tho list of questions 
do not show any very great variation in heating value, and, speaking 
broadly, tho fuel oils used in foundry practice do not show as much 
variation between samples from different sources as do coal or coke 
samples from different sources. d 

RISE IN PRICE OF FUEL OIL. 

In 1911 fuel oil was obtainable in many localities at 2 to 3 cents 
per gallon. In the early months of 1913 the price was, in general, 
5 to 7 cents, and in some cases up to 10 cents or more, but in the 
later months it fell to 4 to 5 cents. Coupled with the change in 
prico has come an uncertainty in deliver}'. In certain sections of 
tho Middle West the main producers of oil have refused to enter into 
contracts for delivery of oil either at stated intervals or stated prices. 
Tho firm furnishing Reply 43 is putting in more furnaces, but is 
installing coal furnaces in preference to oil furnaces, on account of 
tho prico of fuel, although the oil furnaces are to bo kept in use. 
Replies 5, 71, 79, and 197 also show the effect of the increase in price. 

This increase in price has also created a demand for a furnace that 
can be speedily altered from tho oil-burning type to one burning 
coke or coal, so as to be ready for production if the price of oil rises 
so far as to prohibit its use with that fuel. The rise in oil has given 
a decided setback to the makers of oil furnaces and oil burners. 
Furnace users are inclined to sit by and see what developments occur 

o Waterhouse, O. B., Liquid fuel and its application to the foundry: Metal Ind., voL 5, 1907, p. 299. 

& Editorial, Substitute for fuel oil: Foundry, vol. 41,1913, d. 251. 

c Sherman, II. C., and Kropfl, A. II., Calorific power of petroleum oils and the relation of deiaity to 
calorific power: Jour. Am. Chem. Soc., vol. 30,1908, p. 1628. 

d Robinson, F. C., Manufacture of petroleum products: Met. Chem. Eng., vol. 11, 1913, p. 3*9. 



FURNACE FUELS. 


185 


in the oil market beforo changing from some other fuel to oil. It is 
not the present high price that deters them so much as the uncer¬ 
tainty of deliveries and the fear that the price has not reached a stable 
figure. 

The price of coal and coke has, in general, risen also, so that the 
percentage increase in the price of oil over anthracite or coke is not 
so great as its own percentage increase in price. 

That so few melters of brass have abandoned oil furnaces during 
the period of increase in price is the best testimony as to their value 
for the purpose. 

Sperry ° states that, in spite of the doubling in price of fuel oil, 
plants are constantly being equipped with oil furnaces for melting 
and annealing, and deduces that the fact that users have stood a 100 
per cent increase in price shows that there are greater advantages 
in oil furnaces than has been generally admitted. However, the 
higher cost, together with the increase in the prices of copper, tin, 
and zinc over those of 1911, has stimulated interest in the study of 
brass furnaces, both as regards fuel efficiency and metal losses, and 
in the use of electric furnaces for melting brass. 

The reasons for the increase in the price of oil are variously ascribed 
to increase in the consumption, particularly of the gasoline and 
lubricating oil fractions, over the supply and to trust action. It 
seems likely that to some extent, at least, the rise reflects the con¬ 
dition that the value of refined products that can be made from 
the oils previously used as fuel so far overbalances the cost of pro¬ 
duction that it is an economic loss to use the oil for fuel purposes 
at the prices formerly obtained. 

In this connection Finney b makes the following statement: 

The waste in the petroleum industry comes principally from its wrong utilization. 
In the face of the approaching exhaustion of our petroleum industry, it would be well 
to limit the use of petroleum to the purposes for which it is necessary and for which 
no substitute can be found. It is for this reason that it can well be said that the use 
of nearly 19,000,000 barrels of crude oil burned as fuel in locomotives in 1907, at a 
price which brought not more than a hundredth part, and perhaps as low as a thou¬ 
sandth part of its value for high-grade petroleum products, and also our tremendous 
export business in oil, are serious economic mistakes. 

One steel foundry has changed from oil to producer-gas fuel on 
account of the scarcity and high price of oil. c 

That the problem of the fuel-oil supply is serious is shown by the 
appointment of a committee by the American Society of Mechanical 
Engineers to compile data as to the relative merits of fuel oil as 

n Sperry, E. S., Fuel oil and the brass industry: Brass World, vol. 9,1913, p. 191. 

b Finney, J. II., Conservation of natural sources of power: Trans. Am. F.lectrochem. Soc., vol. 17,1910, 
p. 61; see also Day, D. T. (In discussion): Trans. 7th Int. Cong. App. Chem., 1910, p. 102. 

e Anon., Improvements at the plant of the Falk Company: loundry, vol. 41, 1913, p. 325. 




186 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 

compared with other fuels for various purposes, with the ultimate 
view of conserving its use as much as possible for those industries 
in which it has marked advantages over other classes of fuel. 

The rise in price will result in curtailing the use of fuel oil for pur¬ 
poses for which some other fuel is really better adapted, but it hardly 
seems that brass melting falls in that category. 

Whether the development of the Mexican oil fields, concerning 
which Best 0 is optimistic, and the increased availability of the 
California oil through the opening of the Panama Canal will relieve the 
situation remains to be seen. It hardly seems likely that the price 
will soon fall to the 1911 level, and the possibility of even higher prices 
can not be overlooked. 

The advantages of oil fuel are such that the call for it will probably 
result in fuel oil of some grade being available, even though at high 
prices, for brass melting. Deliveries have been better in 1913 than 
were expected late in 1912. 

The Mexican and California oils, in localities to which freight 
charges are not excessive, will seemingly come into wider use. In 
this event existing types of burners must either be modified to handle 
these heavier, more viscous oils, or the oils must be preheated before 
passing to the burner. Preheating 6 is common on the Pacific- 
Coast, and will doubtless be more widely done as the density of the oil 
available increases. 

Irish c makes the following statement: 

The supply of fuel and gas oils must necessarily be a function of the crude-oil pro¬ 
duction of the world. While the amount of crude oil produced lias within the past 
few years been greater than at any other time since the discovery of petroleum, and 
consequently indicates an ever-increasing supply, we are at present, and have been 
for the last two or three years, suffering from a falling off in our production. We are 
informed that the crude-oil stocks in the United States, east of the Rocky Mountains, 
are decreasing at the rate of about 40,000 barrels a day. 

That means that the supply has fallen off and the demand has increased, until the 
demand has overtaken the production, and we are drawing on accumulated stocks, 
and, so long as that continues, exhaustion of the supply of gas and fuel oil will, of 
course, come nearer. 

But the supply of those oils has been supplemented by the Mexican crude. * * * 

The Mexican crude is new to the refiner, and it would be unsafe and unwise to pre¬ 
dict what can be made from it. We know it has an asphalt base, and is limited in pos¬ 
sibilities for the production of refined products. It means that a large production of 
such crude oil will find its way into the fuel-oil market as rapidly as it can be brought 
into this country. 


o Best, W. N., The science of burning liquid fuel, 1913, p. IK. 
b Best, W. N., op. cit., p. 39. 

« Irish.—(In discussion): Met. Chero. Eng., vol. 11, 1913, p. 394. 





REMARKS ON FURNACE TYPES AND FURNACE PARTS. 187 


TAR. 

Coal tar, water-gas tar, and oil tar form possible fuels for brass 
melting and have a higher heating value per gallon than fuel oil,® but 
their extreme viscosity makes their atomization moro difficult. 
Preheating is vital, and the form of the burner must bo such that the 
particles of solid carbon in the tar will not clog the burner. It is 
said * * 6 that both coal tar (undistilled) and tar oil have been successfully 
used in open-hearth steel furnaces. Coal tar has been used for 
crucible-steel melting, but no actual use seems to have been made of 
it for brass melting. 

Oil distilled from coal tar would be similar to ordinary fuel oil for 
foundry use. No actual use of this on brass in the United States is 
known, but Dahm c describes pit and stationary-crucible furnaces, as 
well as a reverberatory, in which this oil is used in Germany. 

REMARKS ON FURNACE TYPES AND FURNACE PARTS. 

NATURAL-DRAFT OIL FURNACES. 

Although the natural-draft oil furnace is common in crucible-steel 
melting, its use on brass was reported by only ono of the firms that 
supplied data (Reply 198, subdivision 23, of the large table). The 
results reported are extremely favorable as to oil consumption and 
furnace life, unfavorable as to crucible life, and fair as to labor cost 
and loss of metal (red brass) in melting. The melting speed reported 
is slow, being 2.7 hours per heat on No. 40 to No. 100 crucibles, a rate 
that would mean a higher relative loss on a high-zinc alloy. This 
typo of furnace makes hot work for the furnace tender. The oil- 
consumption figures given in this reply are the lowest reported for 
any typo of oil furnace. However, as this type of furnace is well 
known from its wide use for melting crucible steel, if its advantages 
were in general as great as they seem to bo in the particular plant in 
question, the furnace would probably have met with wider use. 

ATOMIZING BURNERS FOR OIL. 

In all other furnaces in which oil is used, some type of atomizing 
burner is utilized. There are four main types of burners: First, those 
atomizing tho oil with steam, ah’ for combustion being supplied by a 
low-pressure blower, or, moro commonly, drawn in by tho injector 
action of the spray; second, those accomplishing atomization by the use 

a Best, W. N., Production of and demand for liquid fuel: Metal Ind., vol. 7,1909, p. 101. The science of 

burning liquid fuel, 1913, p. 18. 

6 11 amor, W. A., Tar as fuel for open-hearth furnaces: Jour. Ind. Eng. Chem., vol. 5,1913, p. 252; Ilansen- 
felder, R., Coal-tar oil in tho foundry: Gas World, vol. 59,1913, p. 21; Chem. Abs., vol. 7,1913, p. 3659. 

C Dahm, A., Neuere Fortschritte und Erfahrungen in der technischon Verwendung dor Toor produckto 
fiir Heiz-Kraft-und Liehtzwecke: Zeitschr. angew. Chem., vol. 25,1912, p. 2049. 



188 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


of ft stream of compressed sir at high pressure, which strikes a stream 
of oil fed ftt low pressure within the nozzle of the burner, forcing the 
oil through ft small orifice, atomizing it, and mixing the spray or 
vapor with the air. Much of the air for combustion is thus supplied 
through the burner itself; the rest is drawn in by injector action. 
The third typo (a combination high and low pressure type) forces 
the oil through an orifice at high pressure, and completes the vapor¬ 
ization by the least possible volume of high-pressure air, and suj>- 
plics the air for combustion at low pressure (about 6 ounces). One 
form of burner has one opening for oil, which is fed at a rather low 
pressure, and another for high-pressure air, the streams meeting 
outside the orifices, and thus atomizing the oil into a fan-shaped 
spray. About one-sixth of the air needed for combustion is thus sup¬ 
plied, the rest being furnished at a pressure of 3 ounces through still 
another orifice below the burner. 

Another form of this typo allows a small volume of high-pressure 
air to meet, within or at the tip of the burner, a stream of oil which is 
partly vaporized by its own pressure (about 30 pounds) as it is 
forced from the orifice, the vaporization being completed by the 
liigh-pressuro air. A concentric tube carrying air for combustion 
surrounds the rest of the burner. 

In the fourth type, the high-pressure oil, low-pressure air type, the 
oil is vaporized by being forced through a small orifice solely by its 
own pressure, which is usually raised by pumping to about 45 pounds. 
Air for combustion is supplied, usually by a concentric nozzle, at a 
pressure of about 6 ounces. 

It must bo remembered that in boiler firing with oil, what is wanted 
for fuel efficiency is complete combustion of tho oil; in brass furnaces 
what is desired is complete combustion of tho oxygen of tho air, so as 
to maintain a neutral or reducing atmosphere within the furnace, 
combined with as good fuel efficiency as can be obtained without 
getting an oxidizing flame. Hence it is desirable that the vaporiza¬ 
tion of the oil be accomplished with the minimum volume of air, for 
if in attempting to regulate the flame to obtain somewhat rapid 
heating, the ratio of air to oil can not bo held to such limits as to avoid 
an oxidizing flame and still to supply enough well-vaporized oil, 
trouble will result. 

If the burner is mounted in the open air and shoots the flame 
through a wide opening in the furnace wall, without any sort of dam¬ 
per to control tho air drawn in by the injector action of the flame, tho 
air supply, particularly if the ratio of oil to atomizing air is also not 
under sufficient control, may not bo sufficiently under control, so that 
it may bo difficult to maintain a reducing flame and still get proper 
atomization. 



REMARKS ON FURNACE TYPES AND FURNACE PARTS. 189 

Whatever bo the type of burner, absolute steadiness ° of both oil 
and air pressure is essential; otherwise the flame fluctuates up and 
down, at times giving an oxidizing atmosphere and at times one so 
strongly reducing that fuel efficiency is out of the question. 

STEAM ATOMIZATION. 

In stationary and locomotive boiler practice, steam is commonly 
used for atomization because it is readily available, and its use does 
away with the need of an air compressor. However, the volume of 
steam required is considerable. The Naval liquid-fuel report states * 6 
that 5 per cent of the steam raised is used for atomization in this type 
of burner. At one copper smelter, the steam for atomization is given 
as one twenty-eighth of that raised.® 

Redwood d gives an example of a burner that used 3 per cent of the 
steam for steam atomization, or 2 per cent to run an air compressor 
when the burner was working on compressed air. 

Mathewson 6 states that in a copper furnace, a burner using air to 
atomize the oil has given better results than the burners using steam. 

Best^ gives the total net saving by the use of compressed air 
instead of steam as 4 per cent. 

It is stated 0 that for very viscous fuels burners using steam are 
preferred because a sufficiently high pressure to vaporize the viscous 
material is obtained, but that burners using air show a higher economy- 

Inasmuch as the use of steam introduces into the furnace just so 
much more gas to be heated, burners using steam are not, in general, 
as desirable as the other types. 

The Naval liquid-fuel report,* made in 1904, states a preference 
for compressed air as compared with steam, and states that low- 
pressure air burners appear to be somewhat more satisfactory for 
marine purposes than burners using high-pressure air, although the 
matter w r as not then considered settled. Redwood, 1 ’ however, in 
1910 states definitely that for marine purposes atomizing the oil by 
forcing it through an orifice under its own pressure, without the use 
of steam or air as an atomizing agent, is best. 

Only one foundry (Reply 61, subdivision 31 of the large table) 
has reported the use of steam as an atomizing agent. The oil con¬ 
sumption (which does not take into account the fuel used for steam 

a Best, W. M., The science of burning liquid fuel, 1913, p. 30. 

6 Report of the United States Naval Liquid Fuel Board, 1904, p. 31S. 

c Mineral Industry, 1911, p. 216. 

d Redwood, B., Liquid fuel: Trans. 7th Int. Cong. App. Chera., 1910, p. 82. 

t Mathewson, E. P., Development of the reverberatory furnace for smelting copper ores: Trans. 8th lnt. 
Cong. App. Chem., 1912, vol. 3, p. 123. 

/ Best, W. M., The science of burning liquid fuel, 1913, p. 26. 

g Anon., Firing with coal tar and water-gas tar: Gas World, vol. 58, 1913, p. 674; Chem. Abs., vol. 7,1913, 
p. 2674. 1 

^Report of the United States Naval Liquid-Fuel Board, 1904, p. 373. 

i Redwood, B., op. cit., p. 72. 



190 


brass-furnace practice in the united states. 


raising) is favorable* in this ease, but the single instance should not 
be taken to prove any superiority of steam atomization, in the face 
of the facts above cited. 

BURNERS USING HIGH-PRESSURE AIR. 

Burners using high-pressure air seem far less capable of easy regu¬ 
lation of the flame to different intensities, with the maintenance of 
a reducing flame, than either the combination, or the low-pressure 
types. All crucible oil furnaces that have been found unsatisfactory 
as to quality of metal produced seem to have been equipped with 
burners using high-pressure air. There has recently been a strong 
tendency among foundrymen to adopt the low-pressure or the com¬ 
bination type of burner in place of the burner using high-pressure 
air. Replies 3, 10, 14, 20, 37, 75, 78, 81, 102, 187, and N all repre¬ 
sent firms that have either run comparative tests of these types, or 
have changed from a system requiring high-pressure air to one 
requiring low-pressure air, and all are strongly against the burner 
using high-pressure air. Not a single instance is known in which a 
user of the low-pressure or the combination type has changed to the 
use of high-pressure air. 

It is cheaper to supply the needed air at low than at high pressure, 
both as regards the power required to run a compressor in compari¬ 
son with that required to run a low-pressure blower, and as regards 
the cost of the compressor as compared with that of the blower. 
Of course, most foundries have a compressor for use with air- 
operated molding machines, air chippcrs, sand blasts, etc., but the 
compressor is seldom of such a capacity that it can handle the inter¬ 
mittent load from these sources and also carry a steady pressure for 
the furnaces. This practice results in a varying pressure at the 
burner, a varying flame, and difficulty in maintaining the proper 
reducing flame. Blowers are so cheap that they may bo installed 
for each furnace or each few furnaces, which thus have a steady air 
supply. 

It is noteworthy that practically all successfully operated open- 
flame, oil furnaces, and most of the reverberatories, use compara¬ 
tively low-pressure air and high-pressure oil. 

Schutz a states that down to the point at which not enough air 
was supplied for combustion the zinc loss from an open-flame furnace 
was progressively decreased as the air pressure at the burner was 
lowered. 

In a paper read before the Verein Deutscher Giessereifachleute, 
Tannings b advocates the use of a burner taking air at a pressure of 


a Schutz, F. II. (In discussion): Trans. Am. Inst. Met., vol. 6,1912, pp. 195, 196. 
t> Lcnninjrs, P., Oelfeurung, System Buess: Oieaserei Zeit., vol. 10,1913, p. 301. 



REMARKS ON FURNACE TYPES AND FURNACE PARTS. 191 


about 7 pounds, but in the discussion on the paper, Felder vigor¬ 
ously opposed the use of high-pressure air. 

Most burners using high-pressure air are very noisy, whereas both 
the combination and the types using low-pressure air are far more 
quiet. One maker claims to reduce the noise of the high-pressure 
type by pointing the oil burner downward at a slight angle on a 
bed of coal or coke that is used in conjunction with the oil. No 
information has been received as to the performance of furnaces 
using both solid and liquid fuel. 

COMBINATION BURNERS. 

Few foundries are known in which the combination burners are 
used, Reply 10 and Reply 134 (subdivisions 28 and 1G of the large 
table) being examples. Both the burners in the foundries mentioned 
are homemade. A similar one is on the market, but its sale for 
brass melting has not been pushed. The makers write: 

Our furnace development has been along the line of heating furnaces rather than 
melting furnaces. We have installed some brass-melting furnaces using oil, but 
have never had a very great success. 

The oil consumption reported in Reply 10 (3 gallons per hundred¬ 
weight) is rather higher than the average, whereas that reported in 
Reply 134 (1.3 gallons) is so far below it as to need verification by 
other users. 

There is no question but that, with oil supply, atomizing air, and 
air for combustion all under control, and much of the atomization 
performed by the oil pressure, the nature of the flame can bo con¬ 
trolled to a nicety with this type of burner. It requires an oil pump, 
a compressor, and a blower, or one more piece of apparatus than is 
required by the type using high-pressure air or by the type using 
low-pressure air. It is unquestionably a better type of burner than 
that using high-pressure air. Whether the extra regulation due to 
the three controls, as compared with two on the type using low- 
pressure air, justifies its use in preference to the latter is question¬ 
able, but if not as good, it runs a close second to the latter type. 

In one type of burner the spray of oil coming through one orifice 
is met by a stream of high-pressure air outside the burner and thus 
volatilized, the oil vapor being then mixed with a third stream of 
low-pressure air. This type, although largely used for purposes 
other than brass melting, has some advantages and some disad¬ 
vantages. It is more applicable to very heavy oils, or tar, and is 
less liable to bo clogged by dirt in the oil or carbon in the tar than 
is the concentric form. However, it gives a fan-shaped spray instead 
of a conical one. The burner is not advocated by the maker for a 
furnace taking only one crucible, but is considered more applicable 


192 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 

to a largo pit furnace containing several crucibles. This humor 
had been used in one plant visited, but had not, however, proved 
satisfactory. The heats were said to bo slow, tho furnace hard on 
the furnace tender, and the flame so oxidizing as to score tho crucibles 
deeply. There was no way to tell whether the fault lay in the 
furnace, the burner, or tho operation. 

BURNERS USING LOW-PRESSURE AIR AND HIGH-PRESSURE OIL. 

It is cheaper in power cost to atomize oil by pumping the practi¬ 
cally incompressible oil and to supply air at low pressure than to 
atomize the oil and supply air for combustion by high-pressure air. 

It is desirable to run the burner into the furnace, not through a 
mere opening in it, an arrangement that allows an unregulated 
volume of air to be drawn in by injector action; the burner should 
preferably run into a mixing or precombustion chamber of some 
design, the air for combustion being supplied by the blower. This 
may bo under regulation, or else a damper or shutter may bo pro¬ 
vided at tho opening, so that the air drawn in may be regulated by 
it. With such a device both air and oil are under good regulation 
and the nature of the flamo is completely under control. 

Tho averages of the data reported for tho low-pressure air type 
do not show any striking difference in metal loss, crueiblo life, or oil 
consumption over those for the high-pressure air type, but the 
comments of tho users who have tried both types go to show that 
with either the combination type or the low-pressure air, high- 
pressure oil type, gas absorption and oxidation being less, the quality 
of the metal obtained is better than with the high-pressure air type 
and the speed of melting is as favorable, oil consumption as low, 
metal loss less, and crucible life longer. 

In classifying high-pressure air and low-pressure air burners the 
dividing lino has arbitrarily been taken as a pressure of 2 pounds 
per square inch, although even with this pressure the burners are 
rather noisy. 

Reply 20 states that burners using a 4-ounce air pressure are 
better than those using a 16-ounce pressure. The most represen¬ 
tative forms of low-pressure air burners take air at 4 to 8 ounces 
and oil at 45 pounds or more. Several of these have followed rather 
closely the form devised by the United States Naval Liquid-Fuel 
Board 0 in which a helix just back of the orifice gives a whirling 
motion to the oil and aids in its atomization. Reply 187 describes 
a homemade burner of similar form, in which a drill is used to 
produce the whirling motion. A high oil pressure is desirable in 
order to produce a fine mist of oil, which will offer tho greatest 


a Report of the United States Naval Liquid-Fuel Hoard, 1904, p. 325. 



REMARKS ON FURNACE TYPES AND FURNACE PARTS. 193 

possible surface per unit volume of the liquid oil. Unless the mist 
is fine and the oil thus well mixed with air, it is impossible to get 
sufficiently complete combustion to give a reasonably favorable fuel 
efficiency without using a large excess of air and thus producing an 
oxidizing atmosphere. 

Tho United States naval liquid-fuel report of 1904 previously 
mentioned gives an extended classification and description of various 
forms of oil burners. Itedwood a also describes several forms and 
Strohra b shows some used in boiler practice. 

COMBUSTION SPACE. 

An oil flame like that of a Bunsen burner is cold near tho burner 
and reaches the maximum temperature near the outer tip. With 
most high-pressure air burners the flame is longer and narrower 
than with most of the combination or the low-pressure air burners, 
so that the hottest part of the flame may be well up toward the top 
of the crucible. The flame from a burner using high-pressure air 
often runs a foot or so above even a small furnace, whereas in the 
combination burner or the burner using low-pressure air it does not 
run out so far and fills the whole furnace chamber more completely. 

Whatever be tho type of burner ample combustion space is needed. 
Tho oxygen must diffuse in through the gases of combustion from 
the burning of the outer layer of each tiny droplet of oil before the 
remainder of the drop can be burned. Hence a certain time is 
needed for combustion. Burners using high-pressure air tend to 
carry the oil out of the furnace before this time has passed. An 
attempt is often made to break up the long flame by directing it 
on the sharp edge of a pear-shaped crucible block, or by placing an 
iron rod in the path of the oil spray as it loaves the burner and 
beforo it enters the furnace. As the hollow cone of mist from the 
burner using low-pressure air and high-pressure oil is wide, and as 
the air entering is at low velocity both space and time for combus¬ 
tion are given, so that fairly complete combustion may be attained 
without the use of too much air. 

Too large a combustion space means a larger furnace, and more 
wall surface from which heat is radiated, so that there is a limit to 
the size. With too wide a furnace chamber the hot gases can not 
all come into contact with the crucible, so that a large part of them 
pass out without doing much good. 

All sorts of devices are used to increase the time that the flame 
or hot gases remain in contact with the crucible or to lengthen their 
path about the crucible. The burner may be introduced tangentially, 

a Redwood, B., Liquid fuel: Trans. 7th Int. Cong. App. Chem., 1910, p. 72. 

fcStrohm, R. T., Burners for oil fuel: Electrical World, vol. 62, 1913, p. 312; Chem. Abs., vol. 7, 1913, 
p. 3222. 

-13 


41712°—Bull. 73—16 




194 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


a desirable arrangement, as it tends to produce a gyrating flame 
which passes about the crucible instead of merely upward along 
its walls. 

Crucibles with a flaring flange at the top or a cover ring with an 
extending flange have been suggested. Such a flange would reflect 
the hot gases downward when they struck it and thus lengthen their 
path. Means for directing the flame against a serrated crucible 
block to break up the flame is another device, or the furnace lining 
may be serrated for the same purpose. It is hard to find refractories 
that will not become covered with slag, thus smoothing the surfaco 
and obliterating the serrations. A construction in which the burner 
is at the bottom of the furnace, pointing upward, so that the flame 
impinges on a crucible block properly suspended and with its lower 
surface spherical has been suggested as a means of breaking up tho 
flame. 

Many forms of baffles between the flame and the crucible, ob be¬ 
tween the crucible and the furnace wall, have been suggested, and 
some of them are in successful operation. Tho furnace chamber is 
sometimes enlarged at one side, so as to be pear shaped in plan, 
with the burner at the top and the crucible placed in tho center 
of the circular part of tho “pear,” thus leaving a combustion chamber 
at the side of the furnace chamber. The flame shoots downward at 
tho side of the crucible to the bottom of tho furnace and then upward 
along the other sido of the crucible. Then, too, the chamber may 
bo oval, with a downward-pointed burner at each side. 

Another form of furnaco is approximately the frustum of a cone, 
with tho larger chamber at the bottom (see note on Reply 103). 
Perhaps the form that is more widely used is an upright, cylindrical 
furnaco chamber for tho crucible; at right angles to this, and entering 
at the bottom of tho furnace, is a shorter preeombustion or mixing 
chamber, in which tho oil and air are mixed, the flame as it reaches 
tho furnace chamber proper being at a fairly high temperature, 
whereas that part of the flame in the mixer is not very hot. 

This is a convenient method of lengthening tho combustion cham¬ 
ber. Another step toward increase in length is the use of a taller 
and narrower crucible than tho common form. Tho tall crucible 
is commonly used in tilting furnaces, and its use is one factor in the 
improvement in fuel efficiency of tilting over pit furnaces. 

Redwood ° (speaking of boiler practice) emphasizes tho need of an 
ample combustion chamber, as follows: 

Whatever system of atomizing may he adopted, the construction of the furnace is 
of the highest importance, and it is especially needful that there should he a combus¬ 
tion chamber of ample size, so that the combustion may reach the stage of the con¬ 
version of the carbon into carbon monoxide before the flame comes into contact with 


a Redwood, B., Liquid fuel: Trans. 7th Int. Cong. App. Chera., 1910, p. 92. 



REMARKS ON FURNACE TYPES AND FURNACE PARTS. 


195 


cooling surfaces. It is also essential that there should not be an excess of air supplied 
to the furnace, for, whereas a little smoke may mean the loss of only 1 per cent of the 
heat-giving power of the fuel, an excess of air may easily cause 10 times this dimi¬ 
nution in heating effect. 


SQUARE OIL FURNACES. 

The use of square oil or gas furnaces taking a single crucible is rare, 
although square furnaces are used at some of the mints. There can 
be no advantage in a square combustion chamber over a round one, 
and such a. construction gives a greater shell area for radiation. 
The two square, pit, oil furnaces covered in the data given in subdi¬ 
vision 17 of the large table show about three times the normal oil 
consumption, but such a great variation is not to bo ascribed to the 
shape of the furnace alone, although that, is one of the factors causing 
the low fuel efficiency. 

OPEN-FLAME FURNACES. 

There is no one detail relating to brass furnaces on which there is 
so much and so marked diversity of opinion as on that of the quality 
of metal that can be obtained from open-flame furnaces. 

Foundrymen are usually either rabid opponents or violent partisans 
of this type of furnace. The brass industry is divided into two 
camps; one considers open-flame furnaces unutterably bad, and the 
other swears by, and not at, them. 

The discussion is still raging, as may be seen by comparing Best’s 
point of view.with that of Parry. Best a says: 

For a number of years oil has been used for the melting of brass and kindred alloys, 
but unfortunately direct-lired oil furnaces were recommended for this purpose, which 
resulted in the alloys, which melt at a lower temperature than copper, being sacrificed, 
thus causing an irreparable loss in metal, to say nothing of the attendant change in 
the composition of the metal. It was indeed a sad day when crucible furnaces were 
discarded for the direct-fired furnace; but now, thanks to the ability and fighting 
qualities of young metallurgists in (or who should be in) every brass foundry, we are 
again returning to crucible melting furnaces. & 

Parry c takes the opposite view and states: 

For the past 10 years at least war has been waged between the believers in the 
open-flame furnace and those opposed to its use for the melting of bronze. * * * 

There is no trick in getting good results with the open-flame furnace, and anybody 
with a modicum of common sense and whose prejudice in favor of the antiquated cruci¬ 
ble furnace is not so strong that it will curdle milk can get them. * * * When 
you get right down to “brass tacks,’' the cost of melting metal with fuel oil in an open- 
flame furnace is so small when compared with crucible furnaces that by its use you 
will save so much money that you can well afford a trip to Philadelphia to laugh at 
the mint. 


« Best, W. N., The science of burning liquid fuel, 1913, p. 130. 

b See also Palmer, R. II., Foundry practice, 1912, p. 277. 

c Parry, W. II., Brass-foundry furnaces: Metal Ind., vol. 11,1913, p. 423. 





H HASS-FIT KNACK PRACTICE IN THE UNITED STATES. 


190 

The number of replies explicitly approving and the number con¬ 
demning the open-flame furnace are of about equal number, although 
many merely report the almost exclusive use of this type, thus tacitly 
approving it. 

Many foundryman, after a somewhat extended trial, have thrown 
this typo of furnace out on the scrap pile, from which it usually is 
rescued by some other foundryman who likes the type. One plant 
using six of this type had to buy only two from the maker, getting 
the other four from his competitor’s scrap piles. 

With such a conflict of honast opinion, it is of interest to determine 
why those who failed did fail, and why those who succeeded did 
succeod. 

Eliminating the instances where the cause of failure was that the 
castings made required such hot metal that the loss of heat duo to 
pouring the metal into a ladle made it impossible to uso a ladle, a 
condition that would count equally against a tilting-crucible furnace, 
it appears that, without known exception, the probable cause of fail¬ 
ure on red brass or any low-zinc alloy was operating this typo of 
furnace under oxidizing conditions, or at too slow a speed; every 
success was probably duo to operating tho furnace under reducing 
conditions and at a rapid rate. 

Tho open-flame furnace is not fool-proof. It demands such a 
burner and such oil and air prossuro as will allow tho use of a reducing 
flame, and probably one considerably more reducing than will 
answer in a crucible furnace. It is essentially a high-speed furnace, 
and should be run as such. 

As the flame is directly over the metal, which has a greater surface 
per unit volume than in crucible types, the opportunities for gas 
absorption and for zinc volatilization are great. However, owing to 
tho fact that tho heating surface is largo and that the heat, does not 
have to pass through a crucible to get to the metal tho speed is also 
great. If tho furnace is operated with a burner giving a suitable 
reducing flame and one that will yet burn oil enough to develop 
sufficient heat, and if the metal is promptly poured as soon as ready 
and the furnace at once recharged, then the melting speed is so great . 
that, on red brass or bronze certainly, and on “half yellow and half 
roil ” almost as certainly, the gas absorption and the zinc loss per unit 
weight of metal will be little if any greater than in the old-style pit 
coke furnace. This conclusion the figures reported abundantly prove. 

Its advantages are as follows: No crucible cost; low repair cost 
for lining, if properly and constantly patched; low labor cost for 
melting; little strain on the furnace tender; speed; flexibility as to 
size of charge without much change in fuel efficiency; and a fuel 
efficiency superior to oil or gas crucible furnaces. 


REMARKS ON FURNACE TYPES AND FURNACE PARTS. 197 

There are, of course, some classes of work requiring such exceedingly 
hot metal that neither this type, not any type but pit crucible 
furnaces, however fired, will serve. The open-flame furnace, in the 
larger sizes, is not so well fitted for a jobbing foundry requiring small 
heats of alloys differing widely in composition, and it will not prove 
nearly so economical for intermittent heats as for steady running. 

For large plants, using a great volume of the same alloy continually, 
and in which speed of production is the main object, the open-flame 
furnace is excellent. There are in use several types, some home¬ 
made ones as well as those made by various furnace makers. 
Although there are minor points of superiority or inferiority in 
design, the behavior of different forms of the general type is about 
the same. 

The quality of the alloys containing less than 20 per cent of zinc 
from properly run furnaces of this type is satisfactory. The reputa¬ 
tion of the goods, including those that have to stand high pressure, 
such as valves, made by firms using this type of furnace is sufficient 
proof, even without the explicit statements made in so many replies. 
The number of firms using this type is far below the number using the 
other chief types, but it is the large firm that uses this type, not the 
small one, and most firms that use it use a number of them, so that the 
tonnage melted by the open-flame furnace is great. 

This type, incompetently handled, gives unsatisfactory results; 
properly handled, it is satisfactory from nearly every point of view, 
when alloys low in zinc are melted. 

The maker of one form of the type has recently tried increasing 
the number of burners, with encouraging results. This construction 
will probably increase the flexibility of the furnace by insuring an 
adequate melting speed with a flame that is always reducing. It 
seems possible that, although the burners used almost invariably 
require a comparatively high pressure on the oil and a low pressure 
on the air, a burner with even higher oil pressure and lower air pres¬ 
sure, properly designed to give a flame of suitable length and shape to 
fill the melting chamber of the form of furnace used, may give better 
results. 

It is also worthy of note that by using small charges, or, perhaps, 
smaller open-flame furnaces, plants in which many small heats are 
desired, and in which a slight contamination of one alloy by traces of 
the one previously melted will not do harm, could use open-flame 
furnaces with the maximum melting speed for any existing form of 
furnace, and with a better fuel efficiency than in other types of oil or 
gas furnaces. One maker of this type says, “ Small heats in quick 
time produce most satisfactory metal and cost. ” 


198 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


Owing to the lower melting speed, it appears, from the data received, 
that natural gas is less satisfactory in this type than oil, and that city 
gas or the leaner gases, like producer gas, will bo still less suitable. 
With fuel oil at a high price, the rest of the different factors might, 
however, be so disturbed that, even with a lower melting speed and 
a greater metal loss, natural-gas firing of open-flame furnaces might 
be cheaper in the long run than oil firing. 

OPEN-FLAME FURNACES FOR ALLOYS HIGH IN ZINC. 

It will be noted that the discussion of the open-flame furnaces has 
so far been limited to its use for melting bronze, red brass, or half 
yellow and half red (say, 20 per cent of zinc) brass. Whether the 
open-flame furnace is in general a suitable typo for melting yellow 
brass or manganese bronzo is doubtful. There can bo little doubt 
that alloys with a zinc content up to 18 per cent can be handled very 
well in it. Figure 2 shows that up to this point there is some range 
between the pouring temperature and the boiling point. With a zinc 
content of 30 to 40 per cent, however, the range is small, and hence 
the vapor pressure of the zinc and the tendency for the alloy to lose 
zinc are great. Subdivision 33 of the large table shows 10 users of 
open-flame oil furnaces for melting yellow brass and manganese 
bronze; some of the users employ this type mainly for refining scrap. 
One (Reply 94), though giving figures on yellow brass, states that the 
firm represented uses it mainly for red brass, and reports high zinc 
loss. The only user unqualifiedly approving this type for ordinary 
yellow brass is represented by Reply 173. This user pours heavy 
ingot at a low temperature and therefore has more leeway. 

It may be possible that by taking great care to pour the metal the 
moment it is ready that open-flame furnaces, even on yellow brass or 
manganese bronze, may be operated so that the short time allowed 
for volatilization on account of the melting speed may overbalance 
the tendency for the zinc to be carried away from the large surface 
exposed to the waste gases. 

The bulk of the evidence tends to show that careful regulation is 
required in order to keep zinc losses down. The burden of proof is on 
the advocates of the open-flame oil furnace for alloys high in zinc. 
Yet it would not be surprising if the over-all cost of melting even 
these alloys in this way should be lower than in other forms of furnaces 
under not uncommon foundry conditions. Small differences in plant 
conditions may turn the balance either way, so that it is not surprising 
that most replies are unfavorable to its use, that the firm whose 
experience is reported in Reply 192 took a long time before coming 
to an adverse decision, and that the rolling mill furnishing Reply 
173, which pours cold, states that the furnace is applicable to the 
conditions in its plant. 


REMARKS ON FURNACE TYPES AND FURNACE PARTS. 


199 


Subdivision 35 of the large table shows that no firm using an open- 
flame, natural-gas furnace for alloys high in zinc has supplied data 
on the performance of the furnace, and as all considerations lead 
toward the expectation that natural gas or any otner commercial 
gas will not be as satisfactory a fuel as oil for such alloys, such use 
need not be further considered. 

The open-flame furnace has a considerable use in running down 
borings and light scrap, even of high-zinc alloys, but as an even 
more common furnace for this use is the oil-fired reverberatory, such 
use may be considered under discussion of that type of furnace. 

REVERBERATORY FURNACES. 

The reverberatory furnace is essentially adapted for large-scale 
melting, being usually designed for handling upward of a ton of 
metal. In brass-foundry practice it finds its main use either for 
making large castings requiring more metal than would be supplied 
by ordinary furnaces or for refining borings and light scrap into ingots 
that are analyzed and remelted with the addition of such metals 
as are needed to bring the alloy to the required composition, one 
analysis serving for the whole large charge. 

Several reverberatories are known to be in use, usually somewhat 
intermittently, for refining purposes. Little information on the 
operation of these furnaces for refining is at hand. The ease with 
which bulky borings or scrap may be charged and the ease with 
which the slag from the foreign materials in dirty scrap may be 
skimmed ofi in the reverberatory, combined with the greater fuel 
efficiency of a large furnace, make the reverberatory suitable for 
melting such material. 

For melting metal to be cast directly without remelting, the 
reverberatory finds its main application in Government navy yards 
or in private plants making very large castings similar to those 
made in the navy yards. As the large castings are seldom made 
every day, the furnaces are as a rule used infrequently. 

OIL-FIRED REVERBERATORIES. 

Reply 79 covei*s an oil-fired reverberatory used mainly for refin¬ 
ing. A rather high metal loss is shown, but losses in refining are 
naturally higher than in melting ingot or heavy scrap, on account 
of the greater surface of the borings which makes oxidation likely 
before the metal melts, if the flame is at all oxidizing. 

All the replies on the oil-fired reverberatories, except Reply 80, 
show the high fuel efficiency that is to be expected from a large 
furnace. In the foundry represented by Reply 80 the furnace is 
run only intermittently, and difficulty from oxidation is reported. 
Better results might be expected if the furnace were run constantly 


200 BRASS-FURNACE PRACTICE IN T1IE UNITED STATES. 

so that the furnace tender had continual practice in its operation. 
Reply 81 states that the reverberatory is used both for refining ami 
for making largo castings. Reply 82 states a preference for small 
type's of furnaces for ordinary work, but states that with care as 
good results may be obtained from the reverberatory as from other 
types. Reply 83 states that this type is used for large manganese- 
bronze castings. 


SOFT-COAL REVERBERATORIES. 

Only three replies covering soft-coal reverberatones were received. 
Reply 180 covers a reverberatory used somewhat intermittently 
and mainly for large manganese-bronze castings. Reply 202 is 
the only one dealing with the constant uso of this type for red brass 
in ordinary sand-casting practice. The furnace charge is about 1 
ton. The quality of the metal is said to bo satisfactory for the pur¬ 
poses desired, although it is stated that for high-grade bearing 
metal other t}q>cs of furnace might be preferable. The figure for 
fuel consumption is higher than that reported by the other users of 
this typo or than that specified in the literature. The three users 
of coal-fired reverbera tori es show a great variation in fuel consump¬ 
tion, the cause for which is not clear. 

Reply 173 is from tho only rolling mill in this country known to 
bo using a soft-coal reverberatory furnace for melting yellow brass, 
although there are said to be several such furnaces in use for that 
purpose in England and Wales. This mill has such a class of work 
as allows cold pouring; hence the volatilization of zinc due to the 
flame and waste gases coming into contact with the metal may be 
kept low, and the fall in temperature due to ladle pouring is not a 
serious drawback. This firm prefers the tilting, open-flame, oil 
furnace to a tapping reverberatory, if fuel oil is available at a reason¬ 
able price. 

For large-scale work the choice between the two types mentioned 
will depend on the relative price of oil and soft coal, together with the 
actual facts in the disputed question of the effect on the metal 
melted of S0 2 in the waste gases from fuels high in sulphur. 

It has been suggested a that brass be made by melting the copper 
in a large reverberatory’ furnace (a capacity of 20 to 250 tons being 
mentioned), the metal being heated hot enough to allow tapping into a 
2-ton or 3-ton ladle, * * 6 the zinc (and tin or lead in the case of red 
brass) being added in the ladle and the alloy then poured. This 
method is merely an adaptation to large-scale melting of common 

“ Anon., Reverberatory furnaces for brass melting: Foundry, vol. 41, 1913, p. 92; Brass World, vol. s, 

1912, p. 388. 

6 This heating to a high temperature could be done without notable metal loss, owing to the nonvulu- 
tUity of copper. 




REMARKS ON FURNACE TYPES AND FURNACE PARTS. 201 

practice (for example, see note on Reply 164), and should prove 
practical if the zinc may all be added as such. However, it would 
hardly bo applicable to most yellow-brass melting in which a com¬ 
paratively largo quantity of gates or scrap must be melted, because 
if the desired quantity of this alloyed material v T ere put into the 
large furnace with what new copper is to be used, conditions would 
be as favorable for zinc losses as under the present practice. 

Ellis a states that an open-hearth furnace that utilized the waste 
heat for preheating the air supply would be most useful for melting 
bronze. 

LARGE FURNACES FOR ROLLING MILLS. 

The yellow-brass rolling mills, as a whole, have kept to square, 
natural-draft, pit, coal furnaces, with a charge of about 200 pounds. 
In an industry in which the plants average so large and turn out 
such huge tonnages, it is exceedingly strange that such a slow, 
small-scale method of melting with an expensive fuel has been 
retained. There are two explanations, either of which may be 
correct—first, that the pit, coal furnace gives a quality so much 
higher and a melting loss so much lower that it is, in over-all cost 
and efficiency, the best; second, that the great conservatism of the 
industry has prevented the experimental work necessary to justify 
the exchange of a method of melting known to produce satisfactory 
results for any other that has not yet proved its value in actual 
practice. 

Some progressive mills take a great interest in the possibility of 
obtaining lower melting costs and have a high grade of engineering 
and metallurgical talent at work on the problem. Still, taking the 
industry as a whole, the amount of experimental work being done 
on furnaces is small. That some progress has been made is shown 
by a marked trend of opinion toward round furnaces and away from 
square ones, by the use of coke in some mills instead of coal, and by the 
use of larger crucibles in pit fires by one mill (Reply 1S9), of a forced- 
draft, tilting, coke furnace in another (Reply 79), of an open-flame 
oil furnace in another (Reply 192), and of open-flame, oil, and oil 
and coal reverberatories in still another (Reply 173). 

Although several rolling mills have tried crucible oil furnaces and 
discarded them, one firm is using tilting oil-fired furnaces, eacli having 
a capacity of 600 pounds, and is pouring the metal directly into the 
molds, which are brought to the furnaces, no ladles being used. This 
firm may be said to have passed the experimental stage in its work 
on this type of furnace, as a battery of about a dozen furnaces is run¬ 
ning 24 hours a day. 


« Ellis, A. B. (in discussion): Met. Chem. Eng., vol. 11, 1913, p. 413. 




202 


UHASS-FURNACE PRACTICE IN THE UNITED STATES. 


The practical use of this form of furnace is made possible by pro¬ 
viding covers for the crucibles. r I he covers differ from ordinary flat 
crucible covers by having the form of a hollow cylinder with one end 
closed, and are put over the crucibles just as a cover is put on a tin can. 

The gross melting loss on yellow-brass scrap is given as 1.8 per 
cent, this figure being based on several days’ run on nearly 20 tons 
of metal. The average gross melting loss of the same firm on yellow 
brass when the ordinary pit coal furnaces were used without covers 
for the crucibles is given as 3 per cent. 

The quality of the metal from these oil-fired furnaces is said to be 
exactly as good as that from the coal-fired furnacas. No data on oil 
consumption are available. 

Owing to the uncertainty in regard to the price and the regular 
delivery of fuel oil, this firm is not, however, planning to replace its 
coal-fired furnaces by furnaces using oil, although under present 
conditions it finds the use of oil an advantage. Another reason 
given by this firm for not replacing coal by oil is that it expects the 
early perfection of electric furnaces, the advantages of which are 
expected to outweigh those of the oil-fired furnaces. 

One other mill (Reply 95) has tried a large reverberatory (probably 
fired with producer gas) without commercial success, and another 
(Reply 36) has tried pit, oil furnaces, also without commercial suc¬ 
cess. Further work on pit or tilting oil furnaces with burners using 
low-pressure air and on forced-draft tilting coke furnaces would, 
howevor, probably show many plants in which the use of one or the 
other of these types would be distinctly advantageous. The chances 
are also good for finding many plants whose conditions would justify 
reverberatories, either coal or oil fired, or open-flame oil furnaces, 
whereas only few plants are now using them. 

The opportunity for further experimental work is great, especally 
when the somewhat similar industry of copper refining, in which 
huge reverberatory furnaces, coal or oil fired, are the invariable rule, 
is contrasted with the brass-rolling industry, with its slow heats of 
200-pound charges. If any method of large-scale melting that will 
give a higher fuel efficiency, with a satisfactory quality of metal and 
a low melting loss, is practicable, then the rolling mills show r a great 
preventable waste of our supply of anthracite. From another point 
of view, if methods of melting are available, even at a higher cost for 
the heat units required, that will reduce the losses of zinc, small in 
percentage, but huge in the aggregate, then the rolling mills show a 
preventable waste of zinc that can not be viewed with complacence. 

What, then, are the reasons ascribed for the use of pit coal fur¬ 
naces ? They may be summarized as follows: 

a. The furnaces take little attention during the heat; that is, there 
Is little or no recoaling. 


REMARKS ON FURNACE TYPES AND FURNACE PARTS. 203 

b. Large-scale melting produces segregation of the melt. 

c. Large-scale melting involves ladle pouring and requires too high 
a temperature in the furnace, conditions that cause a high zinc loss, 
or else involve pouring direct from furnace to mold, a procedure that 
is mechanically impractical with a large furnace. 

d. Other types of furnaces do not give a quality of metal suitable 
for rolling. 

e. These furnaces give a lower zinc loss than other types, owing to 
the velocity of the waste gases being comparatively slow. 

Reason a is a minor one, as it is granted that the labor cost per unit 
weight of metal melted would be less in larger and speedier furnaces. 

Segregation of copper to the bottom of the melt, giving the first 
ingot poured too high and the last too low a zinc content, is a func¬ 
tion of the depth of the molten metal, and if metal from a large fur¬ 
nace with a hearth carrying molten metal to the same depth as that 
in the crucible be used, the metal being tapped first from the center 
and later from spouts progressively lower down into ladles the same 
depth as the crucibles now used, there can be no greater segregation 
than at present. 

Pouring from a ladle is considered undesirable in rolling-mill 
practice for two reasons: First, there is danger of greater oxidation 
from the doublo pouring into and out of the ladle; and second, the 
molten metal may be chilled too much by the double pouring through 
the air, and by the ladlo itself. Inasmuch as it is common practice, 
when very large ingots have occasionally to be poured, to melt the 
metal in the ordinary small crucibles, pouring into a larger one and 
from this into the large mold, the difficulty from oxidation is probably 
not a vital one. 

The drop in temperature is a more serious matter. However, 
Replies 79, 173, and 192 show that ladle pouring is possible on metal 
that does not have to be poured too hot, as such pouring is being 
done by the firms represented. Replies 141, 203, S, and T, as well as 
the opinions of several other rolling-mill men, expressed in conver¬ 
sation, indicate that ladle pouring would not be impractical for the 
greater part of the work of the average mill. It is generally thought, 
however, that ingots of a weight less than 150 pounds could not be 
poured from a ladle. 

Ladles are, of course, heated before the metal is poured into them, 
the heating being sometimes done in a pit fire, occasionally by the 
waste heat from the furnaces, sometimes by an oil or gas flame—usu¬ 
ally pointing downward, and burning inside the empty ladle—or, in 
one foundry at least, in a large oil-fired furnace of the reverberatory 
type. 

The ladles are seldom heated as hot as the metal, and, whether 
use is made of an ordinary crucible as a ladlo or of an iron ladle 


204 BRAS8-FURNACE PRACTICE IN THE UNITED STATES. 

with a refractory lining, they lose heat rather rapidly. It would 
seem probable that there might be devised a ladle light enough to 
bo fully portable, which would bo heated, not only before it receives 
the metal, but also during pouring. A portable furnace has to be 
rather small, or else the tilting mechanism has to be very sensitive, 
in order to allow easy regulation of the stream in pouring. To get 
a high fuel efficiency, the walls have to be so thick, in order to obtain 
proper insulation, that the furnace may easily become too heavy to 
be readily portable, even by crane. Moreover, the furnace is not 
working at its proper task, that of melting, while being carried to 
and from the mold. 

A heated ladle, not so heavily insulated as a melting furnace, 
might, however, be made that would bo readily portable, and would 
still supply enough heat during the time of carrying to the mold 
and of pouring either to compensate fully for the loss of heat by radi¬ 
ation that would otherwise tako place, or to decrease very con¬ 
siderably the rate of cooling. 

The most desirable method would perhaps be to use one or more 
heated ladles, or fore hearths, light enough to allow delicate regu¬ 
lation of the tilting mechanism, into which some large-capacity fur¬ 
nace could bo tilted or tapped. The molds would then bo carried to 
the ladles mechanically, as on an endless chain, stopping just long 
enough at the ladle for the metal to bo poured into them. Jtist how 
far the pouring might be made automatic and mechanical is a ques¬ 
tion, but more difficult mechanical problems have been solved. 
Copper ingots, anodes, and wiro bars are poured from reverberatory 
furnaces by methods somewhat closely approximating the ono out¬ 
lined for handling brass. 

In somo iron foundries, particularly those making radiators, me¬ 
chanical transportation of the molds is highly perfected. Ono large 
iron foundry, with a variety of output, carries the molds to the 
furnaces on a long endless train or moving platform running on an 
elliptical track. The metal is tapped into ladles from the cupolas 
and is then carried over the moving platform on ail overhead trolley 
which has the form of a loop, so that the empty ladles come back to 
tho cupola for refilling. 

A somewhat similar plan, but ono in which the molds are brought 
to tho furnaces by overhead trolley will bo used in a new foundry 
now under construction by a firm making brass and bronze castings 
in sand. 

Carrying the furnaces bodily to tho mold by crano has been often 
suggested, and is said to bo done in ono French brass foundry. Such 
a method, or that of putting tho furnaces on wheels and bringing 


REMARKS ON FURNACE TYPES AND FURNACE PARTS. 205 

thorn to the molds on a track, though tried to a small extent in this 
country, has not met with favor. 

Carr,® however, has recently advocated the use of small open- 
hearth furnaces, of such design that they may bo carried to the 
mold, for use in steel foundries. 

There is no reason for believing that simply because metal is 
usually carried to the mold in a crucible or ladle conditions in many 
foundries may not warrant the molds being brought to the furnace, 
or the furnace to the molds. 

If it bo true that no known large-capacity furnace can produce 
metal of a quality suitable for being rolled, that in itself settles the 
question, but all that can bo said on this is that some mills have 
found moro difficulty in rolling metal melted in the largo furnaces 
they have tried than in their regular ones. The problem is again 
largely one of operation and plant conditions. At any rate, this 
point is not well enough established to block the way of further 
experiment even on existing forms of large furnaces. 

The claim that less zinc is lost by melting in small quantities in 
pit fires than in larger quantities in other types is more or less valid, 
for ordinary practice, although the difference is shown by the data 
collected (see fig. 21) to be less than is ordinarily supposed. 

If the figures on the larger crucibles represented in Reply 189 be 
omitted, and if Reply 200 be omitted, because it includes figures for 
German silver, the averages of the data given in subdivision 10 of 
the largo table will fairly represent the common rolling-mill con¬ 
ditions on brass consisting of 65 parts of copper and 35 parts of zinc. 

These averages should be compared with the figures of Reply 173, 
given in subdivision 32 of the table. These figures represent a rolling 
mill using a large open-flame furnace. 

The gross melting loss of 2 per cent given by Reply 173 for the oil 
furnace is not strictly comparable with the averago of the coal fur¬ 
naces, for, although the alloy consisting of 60 parts of copper and 
40 parts of zinc is more volatile than that consisting of 65 parts of 
copper and 35 parts of zinc, yet the pouring temperature is lower. 
From the replies in subdivision 10 of the table that give both the 
gross and net losses, the average gross loss on alloys consisting of 
13 to 18 per cent of zinc is found as 3.95 per cent, and the average 
net loss as 2.47 percent, or three-eighths of the gross loss is recovered 
from the skimmings, leaving the net loss equal to five-eighths of the 
gross. Reply 81 states that one-third of the gross loss is recovered 
on yellow brass. 

oCarr, W. M., Some observations on miniature or detachable open-hearth furnaces: Caper presented it 
October, 1913, meeting of the Am. Foundrymen’s Assn, (not yet published). 





200 


BKA88*FURNACE PRACTICE IN THE UNITED STATES. 


The gross losses on yellow brass, if two replies in which data are 
given only on refining Iwirings lx* omitted, are as follows: 


Reply No.— 

Far cent. 

R1 . 

. 6 

aa . 

. 4.7 

04 . 

. 4.7 

189 . 

. 2 

192 

. 3.4 

1%. 

. 4.5 


Average gross loss.**• * 

Five-eightlis of this average gross loss, slightly less than 2.7 per 
cent, may be taken as the average net loss in melting yellow brass 
(not in running down borings) in all sizes of open-flame furnaces. 
This average is not far greater than the figures for alloys containing 
13 to 18 per cent of zinc although a rather greater difference is to be 
expected. Yet, as the melting losses as figured above are based chiefly 
on furnaces with charges smaller than 2,500 pounds, in which the melt¬ 
ing speed is lower and the molten-metal surface per hundredweight is 
greater, the average figures of 4.2 per cent gross and 2.7 per cent net 
melting losses may bo assumed as fully large enough to cover rolling- 
mill practice on high-zinc alloys, especially as the two figures that 
really are on rolling-mill practice show, respectively, 2 and 3.4 per 
cent gross loss. 

As no oil-consumption figure was given in reply 173 for the 2,500- 
pound furnace, it may bo taken from the curve in figure 20 as 1.4 
gallons per hundredweight, as this curve is drawn for alloys both high 
and low in zinc, and as a high-zinc alloy should take even less than 
the average for alloys with both high and low zinc content. 

The comparison between representative large-scale and small-scale 
furnaces for yellow brass then becomes as follows: 


Results of melting brass in large-scale and in small-scale furnaces. 


Source of data. 

Kind of furnace. 

Weight 
ofcharge. 

Time per 
heat. 

Time per 
hundred¬ 
weight. 

Fuel per 
hundred¬ 
weight. 

<«ross 

melting 

loss. 

Net 

melting 

loss. 

Replv 173. 

Open-flame oil.... 

Small pit coal. 

Pounds. 

2.500 

Hours. 

1.8 

Hours. 

0.072 

Gallons, 
a 1.4 

Per cent. 

a 4.2 

Per cent. 
<>2.7 

Avenge of replies in 
subdivision 10 of 
large table. 

200 

1.9 

0.950 

Pounds. 

33 

3.1 

1.92 

-:- 




« Assumed. 


It would take about 13 of the small furnaces to produce metal as 
fast as the one large furnace would produce it. Subdivision 10 of the 
large table shows that the average life of the lining of the small fur¬ 
naces is 800 heats, whereas the figure given for the open-flame furnace. 































REMARKS ON FURNACE TYPES AND FURNACE PARTS. 


207 


750 heats, is rather lower than the average. It may therefore be 
rougldy assumed that the cost for furnace repairs in each type will 
not be notably different. The labor charge will, in general, be con¬ 
siderably less with the larger furnaces, but as exact figures are not 
available for mill conditions that are comparable for both types, 
figures for this charge must be omitted. 

The average life of the crucibles in the small furnaces represented 
in subdivision 10 of the large table is 34 heats. At the ordinary price 
for a No. 70 crucible, this life means a crucible expense of about 2.5 
cents per hundredweight. The prices of fuel will vary with the local¬ 
ity, but for comparison it may be assumed that the locality is such 
that $6 per ton for anthracite coal and 6 cents per gallon for oil are the 
ruling prices, giving 8.25 cents for coal and 8.4 cents for oil per 
hundredweight of metal melted. 

The zinc loss in the coal furnace, with zinc at 5.6 cents per pound, 
is 10.75 cents, whereas in the open-flame furnace it is 15.12 cents. 

The costs per hundredweight, exclusive of labor charges, would be 
as follows: 


Cost of melting brass in representative large and small furnaces at assumed prices of fuel. 


Kind of furnace. 

Cost of 
fuel. 

Value of 
zinc loss. 

Crucible 

cost. 

Coal. 

Cents. 

9.90 
8.40 

Cents. 
10.75 
15.12 

Cents. 

2. .50 

Oil. 

(lain or loss in coal furnace. 


-1.50 

+ 4.37 

-2.50 



Total saving per hundredweight of metal in coal furnace, 0.37 cent. 


The advantage of 37 cents per hundredweight, exclusive of labor 
charges, for the present type of furnaces should be slightly increased 
on account'of a small charge for power to run the blower and oil 
pump for the oil furnace and for interest charges on the greater cost 
of the oil furnace and equipment, and should be slightly decreased 
by the greater rental charge for the greater floor space occupied by 
enough coal furnaces to give the same output as with the oil furnace. 

Were similar figures given on red brass in ordinary sand-casting 
practice it would probably be found that at the fuel prices given and 
with similar metal losses in both types of furnace, the advantage would 
be on the side of the large open-flame oil furnace, because the foun¬ 
dries in general do not get quite as low a coal consumption per hun¬ 
dredweight as do the rolling mills and the labor cost for melting 
Ls less (metal melted per furnace tender per hour being greater) in the 
larger furnace. This relation is substantiated by the tabulated data, 
which indicate that on alloys low in zinc the average quantity of 




















208 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


metal melted per hour per furnace tender in the common sizes of 
pit-coal or coke furnaces, with natural or forced draft, Ls between 
350 and 450 pounds per hour; in the pit, oil furnaces 450 to 550 
pounds; in forced-draft, tilting, coke furnaces, about 700 pounds; 
in tilting-crucible, oil furnaces 500 to 700 pounds; and in open-flame, 
oil furnaces or reverberatories about 1,000 pounds. 

The cost figures given are not to be taken as exact or actual ones 
and are cited only in order to give a more concrete idea of the relative 
amounts of the main expenses of melting and how each of these will 
vary with change in conditions. 

If the cost of oil remained at 6 cents per gallon, the price assumed 
above, and coal rose to $7.50 per ton, the advantage would amount 
to 2.1 cents per hundredweight in favor of oil. If oil then rose to 8 
cents per gallon, coal remaining at $7.50 per ton, the advantage 
would become 0.7 cents per hundredweight in favor of coal. 

If the zinc loss in the oil furnaces were reduced from 2.7 to 2.2 per 
cent, that in the coal furnace remaining the same, the advantage, at 
the three ratios of fuel cost noted above, would be on the side of the 
oil furnace by 2.43, 4.9, and 3.5 cents, respectively. 

Thus it takes little change in any of the factors to alter the balance 
in favor of one type or the other. As stated at the beginning, there 
is no “best 1 * furnace, as the choice depends on the combination of 
so many variables that are affected by the locality of the plant and 
by its own shop conditions. 

However, the loss of metal in melting is almost invariably the 
highest of the four main items of melting cost, which usually rank in 
the following order: Loss of metal in melting, labor charges, fuel, 
and crucible cost. 

Hence if a furnace can be found that, while producing the right 
quality of metal, will decrease the metal loss notably and lower the 
labor charges and crucible cost somewhat, even though it involves a 
higher fuel cost, it will be an economical one. 

But the discussion of the curves for the boiling-points of copper- 
zinc alloys and the efTect of the volume of the products of combustion 
on the volatilization of zinc has shown that there is little hope of 
developing any type of fuel-fired furnace that will give sufficiently 
lower metal losses than do existing types when properly run to pay 
for other disadvantages. The only method of developing heat in a 
furnace that will not involve the continuous passage of waste gases 
over the metal, continually sweeping out the zinc, is that of electric 
heating. It is therefore necessary to consider the perfection of elec¬ 
tric furnaces for brass melting as the probable main line of improve¬ 
ment in melting equipment. 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


209 


POSSIBLE IMPROVEMENTS IN FURNACES AND 

ACCESSORIES. 

DEVELOPMENT OF THE ELECTRIC FURNACE. 

METAL LOSSES IN THE ELECTRIC FURNACE. 

With electric heating it is easy to design a furnace that will either 
be perfectly gas tight, or so nearly so that the passage of air or gases 
over the metal will be exceedingly slow. That is, the furnace can be 
closed tightly enough so that not much more zinc vapor will bo lost 
than that theoretically corresponding to the partial pressure of the 
zinc vapor from the particular alloy used at the highest temperature 
within the furnace. 

The maintenance of a neutral or reducing atmosphere in the 
melting chamber will also be fairly easy. Hence volatilization, oxi¬ 
dation, and gas absorption can undoubtedly be brought much lower 
than in any other type of brass furnace. Sulphur, of course, would 
be wholly eliminated. Moreover, as far as getting a low melting loss 
and a good quality of metal is concerned, the electric furnace should 
be more “foolproof” than any existing type. Although, with fuel 
furnaces, the leaving of metal in the furnace too long (“soaking” it) 
involves high melting loss and gas absorption, soaking in the electric 
furnace, though undesirable as regards production and power con¬ 
sumption, should have little or no bad effect on the quality of the 
metal. 

The speed of melting in an electric furnace is great. With fur¬ 
naces of the size of the open-flame or reverberatory furnaces now in 
use the speed can, if desired, be made considerably greater than in 
those types that, for speed, stand at the head of present types. In 
small crucible furnaces, say with a capacity up to 300 pounds, the 
speed, and hence the output, can easily be made three or four times 
that of the present average. 

If furnaces of the same size be compared, the labor cost of melting 
in electric furnaces should be lower than that in any present type, 
because of their easy regulation and also because the heat radiated 
from their exterior is far less. It will doubtless be easier to teach a 
furnace tender to handle an electric furnace so as to produce good 
metal than to teach him how to operate an oil or gas furnace. 

There are two main problems that hinder the rapid development of 
the electric brass furnace, that of obtaining a low enough power cost 
per hundredweight of metal melted to make the other savings over¬ 
balance that item, and that of designing an electric furnace that will 
have a low upkeep cost. The power cost is a function of two factors, 
the efficiency of the furnace and the price for which electric power 
may bo obtained. 

44712°—Bull. 73—16-14 


210 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


The efficiency of a properly designed electric furnace is far and away 
greater than that of any other furnace. Although the efficiency of 
fuel-fired furnaces for melting brass, as has been seen, runs between 
1J and 10 per cent, with an average of perhaps 7 per cent, an electric 
furnace should give 40 to 75 per cent of the theoretical efficiency, 
depending on the size of the furnace and on how constantly it Is used. 

Tho cost of electric power is a more serious factor, but, taking a 
long look ahead, the indications are that although all fuels seem 
bound to rise in price, the cost of electricit} T , produced from those 
fuels, with a growing development of competing electricity produced 
from water power, is not likely to increase at the same rate. A 
steady load, such as that for brass melting would bo, is a desirable one 
for a central-station power plant, and central-station owners are 
taking a keen interest in the development of electric brass furnaces. 

At first, in localities favored with cheap power, tho electric furnace 
will find use for general melting, and in other localities will satisfy 
special conditions, such as melting yellow brass and refining both 
yellow and red brass borings, in which tho metal losses are highest 
at present, and melting metal for a product for which exceptionally 
hot metal is required, as the efficiency of fuel-fired furnaces falls 
off rapidly as the temperature to which tho metal must bo raised 
increases, whereas the efficiency of tho electric furnace does not fall 
so rapidly. Whether tho quality of electrically melted red brass 
and bronze will be enough better than that from fuel furnaces to 
justify the use of tho electric furnaces, under conditions of high 
power cost, on alloys that can be melted with little loss in existing 
furnaces is a question that can bo answered only by commercial 
experience. There are plainly enough plants where, oven at exist¬ 
ing power costs, a good electric furnace should bo able so to compete 
with any present type on over-all cost as to justify the development 
work necessary to bring it to a sufficient state of advancement for 
commercial use. 

The matter of upkeep cost, such as for electrodes and linings, is 
not to bo greatly feared, although it is not simple. 

Both tho brass rolling mill and tho brass-foundry operators are 
watching the development of electric furnaces with keen interest. 
There was scarcely a man interviewed on visits made in collecting the 
data presented in this bulletin who did not express himself as con¬ 
vinced that the electric furnace is tho ultimato typo. In fact, the 
mentors of the brass industry are so inclined to think that tho electric 
furnace possesses every advantage desirable in a brass furnace that 
progress on the problem will bo best served if designers and makers 
of electric furnaces for melting brass will bo conservative in their 
claims and will not put the furnaces on tho market until they have 


IMPROVEMENTS IN FURNACES AND ACCESSORIES. 


211 


boon thoroughly testod. r lho attitudo of furnace usors toward tho 
introduction of electric heating is so favorable that it would bo better 
to accept the delay necessary for the commercial perfection of tho 
electric furnace for melting brass than to run the risk of giving the 
furnace a bad name by putting on the market an inefficient or 
mechanically weak furnace. 

The interest of the foundry industry in electric melting is shown 
by tho comments of Moldenke,® Krom/ Langdon/ Sperry/ Bragg,* * 
and Dean/ 

lhat electric-furnace men have given attention to tho problem 
both as regards theory, and to some extent on an experimental basis 
is shown by the articles of Richards/ Fitzgerald/ Weeks/ Hansen ,i 
( lamer/' Ilering/ Bensel,™ Sperry/ Scott/ and Johnson and Sieger/ 

Of the many possible types of electric furnaces that might be ap¬ 
plied to brass melting, some that deserve closest attention because of 
their manifest applicability to the problem are the indirect-arc fur¬ 
nace, the “pinch-effect” furnace, heated by the resistance of the 
metal itself, and the resistance furnace of reverberatory or tilting 
form, with indirect heating from a resistor, all of which involve ladle 
pouring. To meet the needs of melters requiring metal too hot to 
allow ladle pouring, the crucible furnace of tho lift-out typo, with 
indirect heating from a resistor, should be included. 

The Bureau of Mines is conducting experiments on the design and 
operation of electric furnaces for brass melting, the results of which 
will be published as soon as warranted by the progress of tho work. 
Consequently, further comment on electric furnaces is not fitting at 
present. 


a Moldenke, Richard, Electric furnaces for the foundry: Electrochem. Mot. Ind., vol. 5,1907, p. 160. 
b Krom, L. J., Development of inciting furnaces: Metal Ind., vol. 7, 1909, p. 287. 
e Langdon, P. H., Economics of tho future: Metal Ind., vol. 10,1912, p. 467. 
d Sperry, E. S., Editorials: Brass World, vol. 8,1912, pp. 305, 386. 

t Bragg, C. T., Modern brass-foundry progress: Trans. Am. Brass Founders’ Assn., vol. 4, 1910, p. 43. 

/ Dean, W. R., Discussion: Trans. Am. Inst. Metals, vol. 6,1912, p. 76. 

0 Richards, J. W., Electric furnaces in nonferrous metallurgy: Met. Chcm. Eng., vol. 8, 1910, p. 233. 
h Fitzgerald, F. A. J., A new electric resistance furnace: Trans. Am. Electrochem. Soc., vol. 19,1911, p. 
201; Met. Chem. Eng., vol. 9, 1911, p. 283. 

i Weeks, C. A., Melting nonferrous metal in an electric furnace: Met. Chem. Eng., vol. 9, 1911,p. 363. 
i Hansen, C. A., Electric melting of copper and brass: Trans. Am. Inst. Metals, 1912 (not yet published). 

* Clamer, O. II., and Bering, C., The electric furnace for brass melting: Trans. Am. Inst Metals, vol. 6, 
1912, p. 95; Brass World, vol. 8,1912, p. 357; Foundry, vol. 40, 1912, p. 483; Clamer, G. H., Electric melting 
of copper and brass: Trans. Am. Inst. Metals, vol. 6, 1912, p. 129. 

niering, C., Advantages of small high-speed electric furnaces: Met. Chem. Eng., vol. 11,1913, p. 183. 
m Bensel, F., Versuche zur Vermindemng der Metall verlusto bciin Messingschmelzen: Metallurgie, 
vol. 9, 1912, p. 533; abstracted in Chem. Abs., vol. 6, 1912, p. 3256; Jour. Soc. Chem. Ind., vol. 31, 1912, 
p. 879; Jour. Inst. Metals (British), vol. 8,1912, p. 353: Jour. Franklin Inst., vol. 175,1913, p. 150. 
n Sperry, E. S., An experimental electric-furnace plant: Brass World, vol. 9,1913, p. 356. 
o Scott, E. K., Electric furnaces in iron and brass foundries: Foundry, vol. 4,1913, p. 380. 
p Johnson, W. McA., and Sieger, G. N.. Electric furnaces, their design, characteristics, and commercial 
application: Met. Chem. Eng., vol. 11, 1913, p. 606. 



212 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


USE OF POWDERED COAL. 

Another possibility in the development of brass furnaces is the use 
of iinely pulverized bituminous coal for heating tho furnaces. The 
riso in tho price of fuel oil has caused the suggestion from many 
quarters that powdered coal could be applied to purposes for which 
fuel oil is now used. No brass foundry has yet made a thorough test 
of powdered coal, though one firm, now using mainly open-flame oil 
furnaces, has planned experiments. No tests on which they are ready 
to report have yet been made. 

Ono furnace maker writes as follows: 

We hope at an early date to be able to convince some of the large users of braas 
furnaces that powdered coal is the ideal fuel for the purpose, but it could only be used 
by the larger manufacturers, as it would not pay to put in a coal milling and dis¬ 
tributing plant for the small amount of fuel used in the ordinary brass foundry. 

Pulverized coal has practically replaced fuel oil in rotary cement 
kilns, and Peters ° reports that at one copper smelter the use of 
coal, powdered so that 90 per cent passed a 150-mesh sieve, saved 
15 to 20 per cent of tho fuel used in the direct firing of the coal in a 
reverberatory and was considered a success, although the system 
was not permanently used. Another smelter tried it, but tho flues 
were clogged with tho ash and it was abandoned in favor of the use 
of fuel oil, as the smelter was in a locality where oil was cheap. 
Rawlins 6 states, however, that at one copper smelter a powdered- 
coal fired reverberatory has been in successful use for two years. 
In cement work an oxidizing flame is used, whereas for melting 
brass a reducing flame is necessary. 

Tho regulation of the nature of the flame from powdered coal, 
blown into the furnace through a nozzle or burner by a jet of air, is 
considered by cement men to be as easy as is the regulation of the 
flame of gas. However, most burning of powdered coal is under such 
conditions that complete combustion to C0 2 , even though it involves 
excess air, and hence an oxidizing flame, is attempted. 0 

Bamhurst d states that on account of tho high temperatures of 
the flame when there is no excess of air an excess of 50 to 100 per cent 
is commonly used. 

Raymond e states that to get complete combustion of the coal, 
at least four times the calculated volume of air must bo used. Meade / 
states, however, that pulverized coal may bo burned with almost 
exactly the theoretical volume of air, and that if a reducing flame be 

o Peters, E. D., Practice of copper smelting, 1911, p. 355. 

t> Rawlins, J. W., In discussion on paper by J. Lord, “ Pulverised Coal in Metallurgical Furnaces,” 
Proc. Eng. Soc. Western Pennsylvania, vol. 29,1913, p. 3G3. 

* See Paznour, E., Industrial furnaces: 1906, p. 272 (translated by A. L. J. Queneau.) 

d Bamhurst, H. R., Pulverized coal as fuel: Met. Chem. Eng., vol. 11,1913, p. 127. 

« Raymond, A. W., Pulverized coal as fuel: Met. Chem. Eng., vol. 11,1913, p. 10S. 

t Meade, R. K., Use of pulverized coal for foundry purposes: Trans. Am. Foundrymcn’s Assn., 1910, p. 40. 






IMPROVEMENTS IN FURNACES AND ACCESSORIES. 


213 


desired it may be easily produced. lie states a that the volume of 
the air in thb jet that carries the coal into the furnace is only 20 
per cent of that required for combustion, a statement that would 
indicate that a reducing flame might be readily maintained. 

Wood 6 describes a duplex burner, similar to the concentric burner 
used for oil, which, he states, produces “by far the most flexible and 
economical feed in existence.” By the use of such a burner it should 
be possible to maintain a reducing flame. 

Meade c states that by pulverizing the coal a lower grade may be 
used than is successfully used even in the gas producer. The present 
interest in the use of powdered coal is shown by the fact that three 
papers on that subject, by Meade ,' d Bamhurst,* and Quigley/ were 
presented at the October, 1913, meeting of the Iron and Steel Com¬ 
mittee of the American Institute of Mining Engineers. 

Powdered coal would doubtless give a good fuel efficiency, but in 
respect to zinc losses, because of the volume and velocity of the 
waste gases, would not offer much advantage over any of the more 
common fuels, with the exception of producer gas. Powdered coal 
would hardly bo applicable to open-flame furnaces as now constructed, 
as the blast incident to its use would blow the ash out of the furnace. 
Whether in a reverberatory the formation of a slag on the metal, due 
to the ash of the powdered coal, would entrain metal that would with 
difficulty be recovered from the slag, or whether it would form a good 
cover to hinder volatilization of zinc, can bo determined only by 
experiment. 

The low cost and constant availability of bituminous coal is in 
favor of powdered coal, but the expense of the pulverizing plant 
and the difficulty of keeping the flues from becoming clogged with 
the ash are against it. 

It would seem worth while to try the application of powdered coal 
to reverberatory or open-flame brass furnaces, if the open-flame 
furnaces were provided with exhaust flues to cany off the ash. 

GAS COMBUSTION WITH THEORETICAL AIR SUPPLY. 

The low thermal efficiency of furnaces fired in the ordinary ways 
is largely duo to two causes—incomplete combustion and the loss 
of sensible heat in the waste gases. Less than one-third as much 
heat is developed in burning carbon to CO as in burning it to C0 2 . 

a Meade, R. K., op. cit., p. 44. 

b Wood, W. D., Powdered fuel for locomotives: Ry. Age Gaz., July 4, 1913; Eng.Mag., vol. 45, 1913, 

p. 881. 

c Meade, R. K., Use of pulverized fuel for heating metallurgical furnaces: Trans. Am. Inst. Chem. Eng., 
vol. 1,190S, p. 98. 

d Meade, II. K., The use of powdered coal as fuel (not yet published). 

« Bamhurst, II. R., The use of powderod coal as fuel for metallurgical furnaces: Bull. 82, Am. Inst. Min. 
Eng., October, 1913, pp. 2523-2532. 

/ Quigley, W. S., The uso of powdered coal as fuel (read by E. W. Shinn) (not yet published). 



214 BRASS-FURNACE PRACTICE IN TIIK UNITED STATKB. 

There is a loss of sensible heat in waste gases for several reasons. 
First of all, the hot gases pass through the furnace so rapidly that they 
do not become cooled to the temperature of the charge that is being 
heated; if they did, the waste gases at the beginning of a heat would 
leave a brass furnace at the same temperature as that of the cold metal 
charged and at the end of a heat would leave the furnace at the same 
temperature as that of the molten metal. The nearer to the object 
to be heated the area is in which the heat is developed, the moro of 
the heat goes into the object and the less up the stack. In an ordinary 
crucible gas furnaco, for instance, much of the flame is not close to 
the crucible and the heat from the farther parts of the flame or of 
the hot gases lias to bo transmitted through a layer of flame or gas 
that has been slightly cooled by contact with the crucible. This 
condition means that there is a low temperature gradient throughout 
the furnaco from the outer part of the combustion chamber (assum¬ 
ing the furnaco walls to bo hot) to the crucible. The lower the 
temperature gradient the less rapid the transmission of heat. Hence 
if the same volume of gas could be burned in a cylindrical sheet 
of flame about the crucible, as the heat energy would bo developed 
over a larger area than with a single flame, the transmission of heat 
to the crucible would bo moro rapid. One form of gas burner, 
in order to give moro flame surface, mixes the gas and air and shoots 
it into the furnaco in three or moro small flames instead of the one 
large flame. 

Wien more than the theoretical volume of air is admitted with 
the combustible gas, two effects are produced—dilution of the waste 
gases with the excess air, thus wasting all the energy used in heating 
the excess air up to the temperaturo of the exit gases, and a lowering 
of the temperaturo of the flame itself through the dilution. 

The temperaturo of a flame from a combustible gas and one and 
one-half times the theoretical volume of air is only about two-thirds 
as high as of one with exactly the theoretical amount. Hence, if 
the gas be burned with a deficiency of oxygen or with too littlo 
excess to get complete combustion to C0 2 , not all of the possible heat 
is developed. If it bo burned with an excess of air, the heat is all 
developed, but much of it is wasted through dilution of waste gases 
and lowering of flame temperature by the excess air. It is quite 
possible that what a foundryman calls a “reducing flame” in an oil 
or gas furnace is one in which considerable CO is present and, at the 
same time, some air in excess of the theoretical; that is, both CO 
and 0 2 may be present in the waste gases. This condition is common 
in industrial furnaces when an attempt is made to avoid an oxidizing 
flame. In this quite possible case both causes of low fuel efficiency 
are present. 


IMPROVEMENTS IN FURNACES AND ACCESSORIES. 


215 


If, on the other hand, the theoretical volume of air, and that only, 
could be used, so that the waste gases contained neither CO nor 0 2 , 
t lie highest fuel efficiency attainable with any particular fuel would 
be reached. 

It is usually considered impractical to run an ordinary gas furnace 
with the theoretical mixture of gas and air, because the mixture is 
highly explosive and “strikes back 7 ’ into the burner. Garland,® 
however, claims that by the use of a special system of burner and 
control valves producer gas may be burned with only the theoretical 
amount of air. 

In order to prevent this back-firing, a special form of burner is 
used. There are two forms of such a burner—the M6ker and the 
surface-combustion. 

The Meker burner is a laboratory device that causes complete 
mixing of gas and air and passes them at a high rate of speed through 
a grid, an arrangement that prevents back-firing after the principle 
of the Davy safety lamp. 6 

Small furnaces of this type have been built for laboratory use, 
and in one supplied with compressed air it is stated that 105 grams 
of platinum was melted in 17 minutes. Whether or not such a 
burner in which the grid will not become hot enough to allow back¬ 
firing can be made on a large scale is not known, but at any rate 
no furnace of commercial size using such a burner has appeared on 
the market for brass melting. However, a method of combustion 
has been developed—the so-called surface or flameless combus¬ 
tion—which is said to attain the end of allowing the combustion 
of an explosivo mixture of gas and only the theoretical air supply, 
with prevention of back-firing, as well as the almost complete sup¬ 
pression of actual flame. 

SURFACE COMBUSTION. 

The essentials of surface combustion were described by Lucke c in 
1901. lie mentions a method of “increasing the area of the surface 
of combustion” that is practically identical with that widely advo¬ 
cated in the last couple of years by Bone and his coworkers, Wilson 
and McCourt, and by Schnabel. The method of getting the “sur¬ 
face” combustion is to inject a mixture of combustible gas and air 
in theoretical or nearly theoretical proportions, at a speed greater 
than the velocity of back firing, on a bed of incandescent, granular 
refractory material, or through a porous refractory diaphragm. 

a Garland, C. M., A system of burning producer gas: Iron Age, vol. 92,1913, p. 664. 

b Field, C. G., A novel development in laboratory burners and furnaces: Met.Chem. Eng., vol. 9, 1911, 

p. 222. 

e Lucke, C. E., Surface combustion: Jour. Ind. Eng. Chem., vol. 4, 1912, p. 78. 





210 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


Bono® calls the combustion of a gas under such circumstances 
“flameless, incandescent, surface combustion . tr lie emphatically 
denies that such combustion involves a flame, and considers that the 
incandescent solid material promotes the combustion within its inter¬ 
stices entirely without flame. Macho, 6 Kinzbrunner,® and Teclu, rf as 
well as several engineers in this country who have experimented along 
this lino and with whom the subject was discussed, strongly oppose 
this point of view, considering that the combustion is a true flame, 
subdivided into small flames within and at the surface of the porous 
or granular incandescent body. Webster’s e definition of a flame as 
“a stream of burning vapor or gas emitting light and heat” would 
seem to include surface combustion within the category of flame. 

Whether surface combustion is flameless or not is, however, merely 
a matter of terminology, and has no bearing on the efficiency of the 
process, which is the vital point. 

The industrial development of surface combustion has so far been 
mainly along the lines of small household appliances and of boiler 
firing, in which it is claimed that over 90 per cent of the net heat of 
combustion of the gas is transmitted to the water. 

Lucke / describes very fully its application to household appli¬ 
ances, as well as the principles involved. 

The manufacture of porous diaphragms does not seem to have yet 
reached the point where a diaphragm of the proper degree of por¬ 
osity combined with sufficient refractoriness to withstand the tem¬ 
perature needed for brass molting has been made, the diaphragm 

a Bone, W. A., Surface combustion: Jour. Franklin Inst., vol. 173, 1912, p. 101; Ber. Deutsch. chem. 
Gesell., vol. 46, 1913, p. 5; Stahl und Kisen, vol. 32, 1911, pp. 1095, 1272; Chem. Abs., vol. 6, 1912, pp. 925, 
2996, 3003; vol. 7, 1913, p. 1597; Engineering (London), vol. 91,1911, p. 487; Jour. Soc. Chem. Ind., vol. 29, 
1910, pp. 744, 1138, 1448; vol. 31, 1912, p. 524; Proc. Am. Gas Inst., 1911, pt. 1, p. 565; Jour. Gas Light., 
vol. 118, 1912, p. 432; vol. 121, 1913, p. 242; see also: Schundt, L., Flameless combustion: Gas World, voL 
58, 1913, p. 20S; Chem. Abs., vol. 7, 1913, p. 1597; Blum, It., Flameless combustion and its Industrial 
importance: Zeitsohr. Deutsch. Ing., vol. 57, 1913, p. 281; Chem. Abs., vol. 7, 1913, p. 1797; Blackwell, 
II. C., Surface combustion: Chem. Eng., vol. 16, 1913, p. 91; Ain. Gas Light Jour., vol. 97, 1912, p. 90; 
Chem. Abs., vol. 6,1912, p. 3509; Berthier, A., Catalytic combustion and its industrial uses: Lumiere Elec., 
vol. 19, 1912, p. 236; Chem. Abs., vol. 6, 1912, p. 3322; Benner, It. C., Surface combustion: Min. Sci. Press, 
vol. 104, 1912, p. 336; Chem. Abs., vol. 6, 1912, p. 2995; Ellis, C., Flameloss combustion: Bull. Am. Inst. 
Min. Eng., No. 69 p 1912, p. 3509; Chem. Abs., vol. 6,1912, p. 3509; Am. Gas Light Jour., vol. 97,1912, p. 257; 
McCourt, C. D., Bonecourt process of surface combustion: Electrician, vol. 71, 1913, p. 132; Blum, It., 
Die flanunenlose Verbremiung und ihr Bedeutung fur die Industrie: Zeitschr. ver. deutsch. Ing., vol. 57, 
No. 8, 1913; Metal und Erz., vol. 10,1913, p. 337; Krull, F., Die flainmenlose Oberfliichen verbrenuung; 
Zeitschr., angew. Chem., vol. 26, 1913, p. 401 (Aufsatz); Seager, J. A., Surface combustion: Steam, vol. 12, 
1913, p. 70; Canaris, C., Surface-combustion furnaces: Chem. Abs., vol. 7, 1913, p. 3655; abstracted from 
Feuerungstechnik, vol. 1, 1913, p. 373; Bunte, II., Flamcless surface combustion: Jour, gasbel., vol. 50, 
1913. 

t> Mache, n., Cber die sogeannte “ flammenlose” Gasheizung: Zeitschr. angew. Chem., vol. 26, 1913, p. 
163; Chem. Abs., vol. 7, 1913, p. 2108. 

c Kinzbrunner, C., Surfaco combustion: Met. Chem. Eng., vol. 2, 1913, p. 53; Chem. Abs, vol. 7, 1913, 
p. 3403. Abstracted from Feuerungstechnik, Nov. 15, 1912. 

dTedu, X., Characterization of flame: Jour. Chem. Soc., vol. 104, pt. 2, 1913, p. 757, and Chem. Abs., 
vol. 8, 1914, p. 566. 

• Webster’s International Dictionary, 1901, p. 566. 

/Lucke, C. E., Design of surface-combustion appliances: Jour. Ind. Eng. Chem., vol. 5, 1913, pp. 801, 
960. 



IMPROVEMENTS IN FURNACES AND ACCESSORIES. 


217 


burner being so far applied mainly to household appliances, such as 
toasters, and to the evaporation of water solutions. If a diaphragm 
of sufficient refractoriness and mechanical strength could be made, 
tho diaphragm burner could be suspended over the whole surface of 
the metal bath in a furnace of the reverberatory form. Pending the 
development of such a diaphragm, two methods of applying surface 
combustion to brass melting have been proposed and are outlined 
below. 

One method is to pack the granular refractory material into a 
suitable refractory tube which is placed within the bath of 
molten metal inside the crucible or the melting chamber of the 
furnace. This arrangement is said to be peculiarly effective in the 
case of lead and type metal, the melting being continuous, as 
solid metal is added as fast as molten metal is drawn off. Effi¬ 
ciencies of nearly 70 per cent on lead and of 55 per cent on aluminum 
are claimed for a furnace of this design containing the granular 
refractory in an iron tube.® 

When mechanically possible, internal heating of this sort would be 
highly efficient. Tubes of graphite, alumina, or magnesia have been 
suggested for high-temperature work, but there are great mechanical 
difficulties in designing an internally heated furnace of this sort in 
which the heating tube or tubes do not occupy so large a part of the 
melting chamber as to make the charging, of large ingots for example, 
hazardous through breakage of tho tube. If too little tube surface 
were allowed, the speed of the furnace would not be great enough. 
On the other hand, the waste gases from such tubes could be carried 
otT without involving any flow of gas over the metal itself, an arrange¬ 
ment that would be a great advantage as regards zinc losses. 

The other furnace suggested for such purposes as brass melting is 
very similar to a tilting, forced-draft, coke furnace in which tho coke 
below and around the crucible is replaced by the granular, refrac¬ 
tory material through which the mixture of gas and air is forced. 
This bed of refractory material would, however, not be as tliick as 
the bed of coke in the coke furnace, as tho combustion is said to 
take place within a thin layer at the surface of tho bed. Small fur¬ 
naces of this sort have been built, and it is said 6 that a cold charge of 
cast iron (weight of charge and size of crucible not given) may be 
melted in 10 minutes. 

In these small furnaces the gas and air, in practically theoretical 
proportions, enter tho pipe leading to tho refractory material and 
become mixed, and the mixture is admitted from below into the 
granular, refractory material at a rate greater than that of the prop- 

a Bone, W. A., Oberfliichenberbrennung: Chem. Zeitschr., vol. 36, 1912, pp. 1440, 1.55. 

b Kershaw, J. B.C., Flame less or surface combust ion: Met.Chem. Eng., vol.9,1911,p.629; Chem. V orld, 
vol. 1, 1912,p. 198. 






218 BRA88-FURNACE PRACTICE IN THE UNITED STATES. 

ligation of the explosion waves for the mixture in the pipe, so that 
back-firing is prevented. In larger furnaces it might be necessary 
to have several outlets for the mixed gas and air, in order to have 
approximately the same pressure throughout the mass of granular 
refractory material. The refractory material used must be able to 
withstand the combustion temperature attained with the gas in use, 
which is high with the richer gases, such as natural gas or city gas, 
because tho factors of incomplete combustion and of air excess, which 
decrease the flame temperature in ordinary burners, are not acting 
with surface combustion. For the richer gases the high temperatures 
developed make it necessary to use such refractories as silicon carbide 
(carborundum or crystolon), magnesia, or alumina. Calcined lire 
clay, or ganlster, is said to be suitable for the granular refractory 
material when lean gases, such as blast-furnace or producer gas, 
are used. 

If tho accounts are correct, surface combustion allows tho use of 
only tho theoretical volume of air, although complete combustion is 
attained, a result that means that tho miiumum possible volume of 
waste gases is formed; also it may bo applied so as to give a large 
heating surface close to the crucible. Thus as regards fuel consump¬ 
tion and, to some extent, metal loss, it goes a long way toward 
meeting the requirements for more efficient gas heating than is 
effected in the present type of crucible gas furnaces. If surface com¬ 
bustion can do half what is claimed for it, it is worthy of serious 
consideration, particularly as it should be peculiarly adapted to the 
cheaper gases, such as blast-furnace and producer gas, as well as to 
city or natural gas. Lewes ° states that fuel oil, finely atomized by 
the correct proportion of air, may bo used in surface-combustion 
burners if the granular material is previously heated. 

In view of the foregoing it appears probable that experimental 
work on the application of electric heating, of powdered coal firing, 
and of surface combustion of gases to brass furnaces offers consid¬ 
erable promise, because it is quite possible that there may bo par¬ 
ticular alloys on which, or particular conditions under which, each 
one of the three methods of heating might prove better than any 
method yet applied. 

USE OF HEATED LADLE. 

As the economy of large-scale melting is acknowledged, any means 
of enabling the use of large tilting or tapping furnaces by rolling mills, 
and by those foundries whose class of work is so light that pit fur¬ 
naces are now essential, would bo most desirable. Although there 
may be some work for which the extra oxidation and tho increased 


o I,ewes, v. B., Cantor lectures on liquid fuel: Jour. Roy. Soc. Arts., vol. 81,1913, pp. 666, 690,702. So« 
also McCourt, C. D., Combustion of liquid fuel: Jour. Soc. Chein. Ind., vol. 32, 1913, p. 1097. 




IMPROVEMENTS IN FURNACES AND ACCESSORIES. 210 

fall in temperature from two pourings through the air would prevent 
the use of a pouring ladle, yet there are certainly many plants where 
tho feasibility of ladle pouring would be measured by the fall of 
temperature of the metal while in the ladle itself. A heated ladle 
would enable all molds poured from it to be poured at approximately 
the same temperature, instead of the necessity, as at present, of 
pouring the first ones hotter and the last ones colder than is really 
desired. 

As has been indicated under the discussion of reverberatory fur¬ 
naces for rolling mills, it should not be unduly difficult to devise a 
ladle to which enough heat might bo supplied during the carrying of 
the metal from furnace to mold and during pouring, either to com¬ 
pensate entirely for the loss of heat that occurs in a ladle that is 
heated onl}^ prior to receiving the metal, or at least to greatly de¬ 
crease the rate of cooling of the metal. Such a heated ladle might 
be heated by gas, oil, or electricity, and might be made either fully 
portable or portable through a limited radius, an arrangement that 
would probably be sufficient for rolling-mill use. Hence the devel¬ 
opment of a heated ladle should bo classed among tho tasks of those 
who are endeavoring to improve the efficiency of brass-melting 
devices. 

USE OF PYROMETERS FOR MOLTEN BRASS. 

No matter what type of furnace be used, the greatest efficiency is 
obtained bv taking the metal from the furnace the moment it has 
reached tho proper temperature. Heating the metal too hot, or 
“soaking” it in the furnace after it has once reached the proper 
temperature, delays production by cutting down furnace capacity, 
increases tho danger of oxidation and of gas absorption, increases 
the volatilization of zinc, and is an utter waste of fuel. 

Moreover, for each particular pattern or mold, and for each different 
alloy to bo cast therein, there is some definite temperature at which 
the best results are obtained, or some definite range of temperatures 
outside of which results are not satisfactory. If the metal be poured 
when too hot, a rough or dirty casting may result. If poured when 
too cold, misruns, “spills,” or blowholes occur, or oxides and dross 
that would otherwise have risen to the top of tho ladle in metal not 
too cold may be trapped in pouring and produce a porous casting. 

In some alloys, as tho light aluminum alloys, the greatest strength 
and greatest freedom from cracked castings is obtained by pouring 
the metal when at the coldest temperature at which it will fill the 
mold and bo free from blowholes. In others, like yellow brass or 
manganese bronze, tho evidence tends to show that the metal should 
bo poured when rather hot. In still others, as gun metal, it appears 
probable that poorer results are obtained by pouring either above or 
below a given temperature range. 


220 BRASS-FURNACE PRACTICE IX THE UNITED STATES. 

It Is most desirable that the proper pouring temperature for the 
alloy and mold in use In? determined, and thereafter used, and that 
the temperature to which the metal is heated in the furnace should he 
noted. To attain these ends there must be some method of measuring 
the temperature. Luckily, with brass and bronze, the temperature 
is high enough so that a fair approximation may be made by eye on 
the basis of the brightness of the molten metal. With yellow brass 
the amount of zinc fumes gives an indication of the temperature, 
or an approximation may be made by the viscosity of the metal when 
stirred. 

Some men become skilled in judging temperature after long experi¬ 
ence in melting, whereas some never acquire much ability in the 
matter. Even the most skilled man is often at loss to tell the proper 
temperature by eye on a very dark or a very bright day, or in working 
with an alloy that he has not been using for some time. Therefore, 
some instrument for measuring temperatures that will meet the 
requirements of everyday brass melting, both in the furnace itself 
and at the mold, is badly needed. 

On an experimental scale, when neither time nor cost is so vital as 
in regular work, the problem is satisfactorily met for brass by 
pyrometers using either platinum or base-metal thermocouples, the 
platinum couples being, of course, suitably protected. For ordi¬ 
nary work the problem is far more difficult. It is easy enough to 
get a pyrometer that will indicate the temperature of a pot of brass, 
but to get one that will give a quick enough reading and have a 
long enough life to make it a foundry tool instead of a mere laboratory 
instrument is as difficult as it is desirable. 

The problem has been rather satisfactorily solved for the compara¬ 
tively low temperatures of molten aluminum, and progressive alumi¬ 
num foundries are using pyrometers freely and find them valuable. 
There are half a dozen makes of pyrometers that are more or less 
strongly advocated by their makers for use in the melting of brass 
and bronze, but none of them litis yet shown sufficient rapidity of 
reading combined with sufficient length of life to justify its being 
classed as a desirable foundry tool. Brass pyrometers are still labor¬ 
atory instruments. 

w 

There are perhaps a score of plants in the country that make occa¬ 
sional use of a pyrometer in “checking up the melter’s eye,” or on 
very important work, but the plant is yet to be found in which the 
use of the pyrometer in connection with melting brass has been the 
success that pyrometers for use in melting aluminum have proved 
themselves in the aluminum foundry. 

To repeat, then, the development of a practical pyrometer for 
molten brass and bronze Ls to bo classed as one of the pressing needs 
of the industry. 


SOME FURNACE PROBLEMS AWAITING SOLUTION. 


221 


USE OF AN ACCURATE OIL METER. 

One reason for the variations in the oil consumption per hundred¬ 
weight of metal melted reported by various users is the inaccuracy of 
oil meters, particularly for a small flow under heavy pressure. It is 
generally conceded that there is no meter that will accurately deter¬ 
mine the oil consumed by a single small furnace. 

Barnes a testifies to this lack and suggests putting two meters in 
series, adjusting them to read the same under all conditions that the 
system will have to meet, pumping a large quantity of oil through 
both, taking off the supply to the furnace between the meters, and 
passing the oil from the second meter back to the pump. This pro¬ 
cedure involves pumping much more oil than is needed, and might not 
serve in a system in which the oil is forced by air pressure instead of 
by a pump. 

A reliable oil meter is therefore needed for general work as well as 
for efficiency tests of single furnaces. 

SOME FURNACE PROBLEMS AWAITING SOLUTION. 

There are certain points of both scientific and technical importance 
on which more detailed knowledge would aid investigators of brass- 
furnace design and brass-furnace efficiency. First among these, of 
course, should be named further knowledge as to the properties of 
known alloys and the effect of impurities on them, as well as the 
discovery of new alloys. 6 

Other problems, the solution of which would help reduce waste and 
increase efficiency, are the determination of the proper pouring 
temperature for various alloys and of the actual amount of heat 
required to raise various alloys to a proper pouring temperature; 
development of better refractories for furnace linings; further 
knowledge as to fluxes and molten covers, and as to “reducing,” 
“neutral,” and “oxidizing” atmospheres in brass furnaces. 
Although the terms “reducing flame,” “reducing atmospheres,” 
“oxidizing flame,” and “oxidizing atmosphere” are commonly used, 
and have been used throughout this bulletin to express the idea in 
mind, yet there is no exact knowledge as to what constitutes a re¬ 
ducing or oxidizing atmosphere in a brass furnace. Wider knowl¬ 
edge as to the waste gases from various types of furnaces as well as of 
the fuel consumption, metal loss, speed of melting, and the quality 
of the metal produced when the furnaces are run under more and 
less strongly oxidizing and reducing conditions, would contribute 
much toward better furnace operation. 

a Barnes, E. A., Nonferrous foundry economics and refinements: Trans. Am. Brass Founders’ Assn., 
vol. 5, 1911, p. 98. 

b Whitney, W. R., Alloys: Trans. Am. Brass Founders’ Assn., vol. 5,1911, p. 54; Tarsons, C. L., Notes 
on mineral wastes: Bull. 47, Bureau of Mines, 1912, p. 28. 




222 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


ADVANCES POSSIBLE WITH PRESENT EQUIPMENT AND 

KNOWLEDGE. 


•VIthough further progress in the development of methods of heating 
and improvements in furnace design and furnace accessories, as well 
as the scientific solution of many problems, is desirable, there are 
yet great advances possible in the use of the equipment and knowledge 
now available. Pick out any alloy and any type of furnace and note 
from the table of data the vast difference in metal losses, in speed 
of melting, in crucible and lining life, and in fuel consumption between 
the average practice and the best practice as there shown. 

The improvements possible in tho present average practice may 
be divided into the utilization or recovery of various wastes and the 
prevention of wastes. 


UTILIZATION OR RECOVERY OF WASTES. 


UTILIZATION OF WASTE ITEAT. 

The waste heat from brass furnaces has been utilized in several 
ways—for preheating the metal to be melted, for annealing crucibles, 
for preheating air for combustion, for preheating oil or gas fuel, for 
heating core or mold drying ovens, for foundry heating, for heating 
a steam boiler and thus producing power, and for preheating the 
water fed to the boiler. 

The use of waste heat for preheating metal is found to some extent 
in many foundries. In rolling mills it is common practice to lay 
some of tho ingots of copper on top of tho coal around tho crucible 
in order to preheat them before putting them into the crucible. With 
tilting-cruciblo oil furnaces or with other types in which thero is a 
charging opening, ingots, gates, or large pieces of scrap are often 
laid over tho opening to bo preheated by tho waste gases. This 
heating also allows the breaking up of gates that are too long to 
permit ready charging, as they become brittle when hot and may be 
easily broken as they are being poked into the crucible with a bar. 

Another very common use of waste heat is for heating the storage 
space for crucibles, which may bo a special oven heated by running 
the main Hue through it, or the crucibles may merely bo piled back 
of a battery of furnaces or over the flue. 

One maker of crucibles says: “The best device for annealing 
crucibles is a furnace built expressly for the purpose, using the 
waste heat from the melting furnaces on its way to the stack. These 
can he built so that tho heat can bo regulated and the temperature 
brought gradually up to or above 250° F.” 

With gas, oil, or forced-draft tilting coke furnaces tho ladles 
may be inverted over the tongue of flame at tho top of tho furnace 
and thu9 heated before the metal is poured into them. 


ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 223 

The next stop is the use of a “feeder” or “hood” preheater. 
This is often an old crucible with a hole punched in the bottom and 
is set into the top of the melting crucible, being supported by it in 
pit furnaces or by a special holder or cover ring in tilting-crucible 
oil furnaces or tilting forced-draft coke furnaces. Nearly all of 
the latter are regularly built for a feeder, either an old crucible or a 
special funnel-shaped device of iron lined with a suitable refractory 
being used. In a foundry where crucible melting is done such a 
feeder is much used in refining borings into ingot, as it allows the 
charging of a greater quantity of borings than can be charged into 
the crucible without the feeder. The firm supplying Reply 14 
uses a feeder in melting borings in both oil-fired and coke-fired pit 
furnaces. In Reply 6, representing a plant that uses a tilting, 
forced-draft coke furnace, it is stated that the metal is actually 
melted in the preheater, dropping into the crucible proper, where it 
is brought to pouring temperature. The high fuel efficiency of the 
tilting, forced-draft coke furnace is partly due to the use of the 
preheater. 

Some double, reversing, oil, or gas furnaces are designed with two 
crucibles or chambers, a burner being placed at each end, and metal 
is put in both crucibles or chambers, but only one burner is used at a 
time. The waste gases from the first compartment pass into the sec¬ 
ond before leaving the furnace, thus preheating the metal in the second. 
When the metal in the first one has been melted it is replaced by 
a cold charge and the other burner is lighted. The preheated metal 
in the second and now primary chamber is melted more quickly 
than if it had not been preheated. 

This reversing principle is applied to both open-flame and crucible 
furnaces. Many users of this reversing method of open-flame heat¬ 
ing havo abandoned it on account of the rapid deterioration of the 
furnace lining, which, however, is a fault of the construction of the 
furnace rather than inherent in the method (see note on Reply 187). 
The three replies (Nos. 73, 96, and 204, subdivision 32, of the large 
table) from firms using the open-flame reversible furnace show a 
rather better average fuel efficiency than the general average of the 
single-chamber furnaces of the same size. 

No data are available on crucible furnaces of this type, but one 
maker claims a 25 per cent saving in oil or gas by its use. Best a 
describes an oil-fired reversing furnace for brass melting that takes 
three crucibles in each of two chambers. Each chamber becomes 
in turn the melting and the preheating chamber. This furnace is 
said b to be in successful operation. 


a Best, W. N., The science of burning liquid fuel, 1913, p. 130. 
b Best, W. N., op. cit., title-page. 



224 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 

Iu another method of construction applicable to pit furnace* a 
second crucible is set into a second pit, into which the flue from the 
furnace proper leads and from which a flue leads to the stack. I lie 
second pit may therefore be regarded as an enlargement of the 
flue. The metal in the second cruciblo is preheated by the waste 
gases until the metal in the primary chamber is ready, when the 
first crucible is replaced by the second one with its preheated 
contents. After the metal in the first crucible has been poured that 
crucible is charged anew and returned to the furnace, but this time 
to the secondary chamber. 

Such a furnace heated by oil is described by Krom a who states 

V » 

that the metal in the secondary crucible may be preheated to 800° 
or 1,000°. (It is not stated whether this temperature is in centi¬ 
grade or Fahrenheit degrees.) He gives no figures as to the saving 
in fuel. 

Reply No. 60 (subdivision 6 of the large table) gives data on the 
use of such a furnace fired with coke and coal under forced draft, 
the air supply to both chambers being under regulation. In this 
case the pouring temperatures used are high, and the metal in the 
preheating chamber is brought almost to the melting point, or even 
above it, before the metal in the primary chamber is ready to be 
poured. The fuel consumption reported on this furnace is high, 
but the metal has to be much hotter than in ordinary practice, and 
the report is on a square furnace. It is stated that better results 
had been previously obtained with a round furnace. The user 
states also that the preheating of the metal gives a far greater effi¬ 
ciency than can bo obtained without it. 

A similar enlargement in the flue of a pit furnace is used to heat 
pouring crucibles used as ladles for tilting furnaces in some other 
foundries where both pit and tilting furnaces are in use. 

Another method of utilization of waste heat is for preheating the air 
for combustion in forced-draft coal or coke or oil or gas furnaces, and 
for preheating the gas or oil fuel as well. Such utilization is usually 
effected in one of the following ways: The air pipe is run through 
the exhaust flue, care being taken that by the use of suitable by¬ 
passes only enough hot gases are admitted to heat the pipe to such 
temperature as it will stand without too rapid deterioration; or the 
air pipe is run in a spiral, or in a series of return bonds, in the path 
of the waste gases from a tilting furnace; or the air is passed around 
the furnace shell and within an outer shell (with such an arrangement 
the refractory furnace lining need not be as thick as usual) before it 
goes to the fire box of a forced-draft furnace, or to the burner of one 
fired with oil or gas. 


a Krom, L. J., Development of melting furnaces: Metal Ind., vol. 7,1909, p. 325. 



ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 225 

Oil may bo heated in similar ways, but can not be heated hot enough 
to effect much real fuel saving, as too high a temperature will cause 
the deposition of carbon, which will clog the burner. Preheating 
of oil is mainly to make it fluid enough to flow more readily and to 
atomize more easily. 

The firm supplying Reply 10 preheats both the oil and the air for 
combustion. Reply 15 is on natural-gas pit furnaces with air pre¬ 
heated by being passed around the furnace shells. Reply 108 is on 
a city-gas pit furnace, and Reply 164 is on pit furnaces fired with 
producer gas, in both of which regenerative heating is used. In the 
first furnace the temperature of the waste gases leaving the regener¬ 
ator is said to be 200° F., and in the second the incoming air is said 
to be preheated to about 600° F., the air pipes being kept just below a 
visible red. In the latter furnace there was considerable difficulty 
at first in getting a grade of iron pipe and a method of making expan¬ 
sion joints that would prevent the necessity of frequent repairs to 
the recuperator, but the trouble was overcome. 

Reply 152 covers a tilting oil furnace in which the air pipe leading 
to the burner was given a number of return bends as it passed through 
the hood over the furnace that carries off the return gases. The oil 
pipe is similarly placed, but not in so hot a place. The air, by the 
time it reaches the burner, is heated to 600° F. and the oil to 375° F. 
This furnace shows a high fuel efficiency. The same firm also uses 
a forced-draft, tilting, coke furnace for which the air is heated as in 
the oil furnace, and also by being passed around the furnace shell 
before going into the fire box, thus being heated to a higher tempera¬ 
ture than the air for the oil furnace. The fuel efficiency is below the 
average, but may perhaps be due to having too large a coke space. 

Several methods of preheating the air for combustion, as well as 
the use of preheaters and feeders, are described by Horner a , who 
states that furnaces utilizing waste heat are 50 per cent more efficient 
than the ordinary pit furnace. 

An English furnace of the forced-draft tilting coke type in which 
the air is preheated, both by being passed around the furnace shell 
and by being brought to the furnace by an intake pipo bearing a 
helical fin and running through the flue that carries the waste gases, 
is shown by Horner, 6 and by Marteil.® The helical fin forces the waste 
gases to whirl around the intake pipe, an arrangement that is in¬ 
tended to produce a greater preheating of the incoming air by length¬ 
ening the path of the waste gases about tho intake pipe. A feeder 
is also used on the furnace. 


a Homer, J., Utilizing the waste heat from brass furnaces: Foundry, vol. 41,1913, p. 113. 
b Homer, J., loc. eit. 

c Martcil, V, Alliages et fonderie dc bronze, 1910, p. 97. 


.14712°_Bull. 73—1G-15 





22 (> BRASS-FURNACE PRACTICE IN THE UNITED STATES. 

Reynolds® advises preheating the air supply in open-hearth fur¬ 
naces for melting iron by the waste gases and claims that this would 
effect a saving of 25 per cent of the coal. 

One type of oil-fired converter for steel preheats tho air used for 
combustion by directing tho tongue of flame issuing from the '‘nose’’ 
of the converter into an economizer. The maker of this converter 
states: 

This economizer is an important feature of the plant, serving to recover the waste 
heat arising from the combustion of tho oil during melting. It consists essentially 
of a series of ribbed cast-iron pipes of U-section, through which the blast passes, the 
heat from the vessel passing round and amongst those pipes on its journey to the 
chimney. By this arrangement the cold air delivered from the blower is raised to a 
temperature of about 800° F. before passing to the converter. 

This device should be directly applicable to open-flame brass fur¬ 
naces fired with oil or natural gas. 

It may be confidently stated that any of the preheating devices 
mentioned will considerably increase the fuel efficiency over that 
possible without such preheating. Whether the saving will pay for 
tho cost of installing the necessary additional equipment and of 
repairs is a question depending on fuel cost, tho degree of perfection 
of the preheating device chosen, and the special conditions in tho 
individual plant. In general, the use of preheating devices mani¬ 
festly means a considerable saving. 

The above methods of utilizing waste heat are somewhat directly 
connected with the heating of metal, crucibles, and ladles; that is, 
except for crucible storage, when tho need for tho heat exists only 
when the furnaces are running. 

Besides these methods, there are other ways of utilizing waste 
heat. One of these is in heating ovens for baking cores or dry-sand 
molds. This use has been suggested by Langdon. 6 Barnes c in 
this connection writes as follows: 

In our foundry we have arranged the store room for crucibles, fire-brick beds, and 
other supplies that are likely to be affected by the absorption of moisture in a brick 
vault heated to a considerable degree by the passage of spent furnace gases through 
suitable ducts under the floor of the vault. Shelving is arranged in this vault for the 
storage of cores that have been baked but are not yet required. For a number of years 
we have successfully employed a core oven built in line with the main flue-gas vent. 
The spent gases from the furnaces pass through cast-iron ducts built to constitute 
the floor of the core oven. These ducts are controlled by hinged dampers which can 
be deflected so as to pass the gases directly up the stack. When it luromes necessary 
to bake large cores, the heat in this oven is augmented by the use of an oil burner 
connected to the main fuel system. 


a Reynolds, A., Some fundamental faults of the present-day furnaces and their remedies: Iron an I Steel 
Inst.,May, 1913, meeting, reported in Met. Chem. Eng., vol. 11,1913, p. 413. 
fc Lang don, P. II., The use of brass-foundry gases: Met. Ind., vol. 5, 1907, p. 356. 

« Barnes, E. A., Nonferrous foundry economics and refinements: Trans. Am. Brass Founders' Assn 
vol. 5,1911, p. 95. 





ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 227 

The firm supplying Reply 10 uses such an oven for baking dry- 
sand molds, and reports as follows: 

While we used the waste heat from our pit furnaces in the old foundry to fully 
heat our core ovens, the gases passing directly through it, in our new foundry, where 
the smoke bonnets and other ventilating arrangements were piped into the same 
core oven, the amount of cold air passing in seriously interfered with the heating 
effect of the ovens themselves. For this reason we abandoned this arrangement, 
although if we had put up a separate stack for ventilation and allowed the waste 
heat from 12 or 14 furnaces to go through the oven we would no doubt have ample 
heat. These gases are used now in a measure to keep our crucible storage warm and 
dry, but there is no doubt that with a properly arranged furnace room the wash water 
and the core ovens could be satisfactorily heated. 

The firms represented by Replies 48, 101, 122, and J, which use 
natural-draft, pit, coke furnaces, and the firm represented by Reply 
146, which use pit oil furnaces, heat core ovens with the waste gases. 

The core ovens heated by the coke furnaces are small ones, di¬ 
rectly over the main flue, which has a thin top so as to give as much 
heat as possible to the ovens. The temperature at which the cores 
are baked in the oven is regulated by the distanco the shelves bearing 
the cores are placed from the floor, or by varying the supply of air. 
In oil furnaces, the waste gases are passed directly through the 
core oven on their way to the stack. 

In shops requiring little core work such arrangements are quite 
satisfactory. In putting such a system of core-oven heating into 
a shop where the core work is an important factor and oven room 
not too plenty, some auxiliary method of heating the ovens should 
also be installed, because, although too strong a heat can bo pre¬ 
vented by b}-passes and dampers, if enough furnaces are not being 
run on a given day to bring the oven to the right baking temperature, 
important cores for the next day’s work may be left green, or cores 
of a poor quality may be produced through inability to get the 
proper baking temperature for the binder used. 

If an auxiliary oven-heating system is ready for use whenever 
the waste gases do not supply enough heat, waste-gas heating should 
prove satisfactory, and should almost eliminate the item of expense 
for core-oven fuel. 

Still another use for the waste gases is in heating the foundry in 
cold weather. It is a crying shame that so many foundries are so 
cold in winter that the men can work with neither comfort nor effi¬ 
ciency, and that the sand is cold or even frozen, so that the castings 
show blowholes and other defects due to cold sand, although more 
unused heat is passing outdoors in the waste gases from the furnaces 
than would heat the foundry well. There are two desirable methods 
by which such foundry heating might be accomplished—by indirect- 
air heating, or by steam or hot-water heating. 


22a 


B HA 38-FURNACE PRACTICE IN THE UNITED STATES. 


Tho indirect-air heating, obtained by putting a casing around a 
sheet-iron section in tho base of the stack and blowing tho air to be 
heated through the space between the stack and casing, is said ° to 
give satisfactory results in annealing furnaces and is suggested for 
brass furnaces. 

Some devices, in which the air was passed through iron pipes 
placed in tho base of the stack, have not given satisfaction in this 
country on account of the destroying of the pipes by tho heat and 
the sulphur dioxide from the fuel used. One firm, which uses a 
dozen pit, coke furnaces taking a No. 80 crucible, had such experi¬ 
ence and reports as follows: 

A description of what we endeavor to do with our waste heat from the brass furnaces, 
and which did no 1 : prove satisfactory. follows: 

In building our new plant we constructed a chimney which is a circular affair 
inside and out, 3b inches on the bottom and 24 inches on the top, 60 feet high, with 
two inlets—one on the floor level and one about 12 feet from the floor. The openings 
are 90° from each other. The air channel from the brass furnaces leading into a chim¬ 
ney on the floor level was connected with a shut-off at the chimney and also had a 
shut-off in the middle of the air channel. We had a hot-air furnace made by an 
engineering company who claimed they had the only apparatus in the market for 
handling hot gases which could not be utilized for heating. 

This fnrnace consists of a series of cast-iron tubes about 4 inches in diameter and 
4 feet long. These were inserted into cast-iron plates on either end, and asbestos 
packing was inserted round the tubes on the inside of the plates, and this again held 
tight by a spring cast-iron washer to make it air-tight. On the front end of this fur¬ 
nace we had a 6-foot fan which blew the cold air into the inside of the tubes and 
would come out hot on the other end, which then went through the air duct through¬ 
out the factory. Beneath these tubes we had also a furnace whereby we could heat 
the tubes independent of the waste heat from the brass furnaces, as for instance, at 
night the furnaces are not in use and the night watchman had a fire in this furnace. 
In the day time or about 7.30 when the furnaces wero all going we opened up the 
damper in the furnace channel and let the hot air from the furnaces pass through this 
furnace on the outside of the tube and up to the inlet in the chimney, about 12 feet 
from tho ground. When this was running the shut-off or damper on the floor level 
to tho chimney was shut off. In the evening when we were through melting, the 
damper or shut-off in the furnace was shut off and then we opened up the damper 
connected with the inlet of the chimney. 

This system worked well in moderate weather, but we had this put in two years 
ago, and the first winter we tried it we had an exceptionally cold winter and it did not 
work satisfactorily at a temperature on the outside to more than 10° below zero. 
When the temperature on the outside got lower than that, we could not heat the 
factory properly. 

A second objection, and this was probably the main reason we gave it up, was that 
the company had guaranteed the tube to stand several years without burning up. 
They claimed they had experimented on this for years and had a perfect mixture in 
iron which would stand the excessive heat on the outside and approximately cold 
influx of air on the inside without cracking. It proved, however, that these cast-iron 
tubes cracked the same as any other cast iron, and whenever they cracked it left a 
certain amount of gas in the factory, which was objectionable. During the corre- 

• Bocddieker, O. A., In discussion at a meeting of the Birmingham Section of »he Institute of Metals, 
reported in Brass World, voL 9,1913, p. 13. 






ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 229 

spondence with the firm asking for remedy, they went into the hands of the receiver. 
When the winter was over, the writer decided not to try this again for another winter, 
and we have now installed a heating, plant with a low-pressure steam system and 
having about 7,000 feet of radiation on an area 7 feet by 8 feet by about 6 feet high, 
and the same fan is used to blow the cold air through the pipe and force it through 
the factory as before. This system we think is by far the better, because it distributes 
fresh air from the outside heated to the proper temperature throughout the plant all 
the time, and by having steam coils up above the boiler the condensed steam goes 
back into the boiler again as hot water, without any pumps or traps of any kind. 

However, as iron piping, if not in too hot a place, gives satisfactory 
results in regenerative gas furnaces, the method ought to be 
possible, at least with some fuels. Heating by hot water or steam 
will of course keep the piping cool enough to insure a good life. 
Reidenbach a states that the waste gases from the furnaces of open- 
hearth steel mills contain enough heat to generate sufficient steam 
for the operation of large plants and that he himself, with the waste 
heat of two No. 200-crucible pit furnaces, has maintained a steam¬ 
heating plant carrying heat to the entire offices, at an annual saving 
of $300 in fuel. 

One plant visited had tried such a method, a small boiler being 
placed over the main flue from a couple of pit furnaces, the flue 
taking the place of the ordinary fire box and furnace of the boiler. 
This arrangement worked well while the furnaces were in constant 
operation, but was abandoned because the operation of these furnaces 
became intermittent. However, an auxiliary fire box might have 
been added. 

In another plant visited by the author, waste heat successfully 
heats a large foundry with several wings of a high one-story con¬ 
struction and with a great many windows. Pit, coal furnaces, in a 
large battery, with large main flues leading to the stack, are used. 
The flues have doors at their ends which allow access to the interior. 
Three or four return bends of 3-inch pipe some 15 or 20 feet long are 
placed within the main flue when cold weather begins and are con¬ 
nected with radiator pipes running all over the foundry. Tho 
arrangement is very similar to tho common method of heating water 
for household use in an ordinary hot-air furnace. 

Tho foundry is said to be well warmed in the most severe weather, 
no frozen sand being found, even near tho windows farthest from the 
furnaces. The piping is removed in tho spring, when foundry heating 
is no longer needed. The same pipes have been used for three years 
and appear to bo still in excellent shape. Everyone around the 
plant was enthusiastic over the success of tho system. 

In plants dealing with higli-zinc alloys any method of utilizing 
waste heat should allow ready access to any part of the system, thus 

a Reidenbach, F. W., Waste heat: Trans. Am. Brass Founders’ Assn., vol. 3, 1909, p. 17; Metal Ind., 
vol. 7, 1909, p. 219. 





230 brass-furnace practice in toe united states. 


permitting the removal from time to time of any zinc oxide that 
might collect on the pipes and, by insulating them to a degree, cut 
down the amount of heat furnished. 

The chief remaining method of utilizing waste heat is in steam 
raising for power purposes, or in preheating water fed to the boiler 
of the power plant. 

Tho use of inclined or vertical water-tubo boilers, economizers, and 
feed-water heaters in the stacks of open-hearth steel furnaces, pud¬ 
dling furnaces for melting iron, and reverberator}' copper-melting 
furnaces is generally well known. A paper 0 on tho generation of 
steam by tho waste heat from furnaces was presented at tho October, 
1913, meeting of the Iron and Steel Committee of the American 
Institute of Mining Engineers. 

Tho waste gases from cement kilns havo also been used for steam 
raising. 

Schreiber 6 describes tho use of such devices in connection with 
open-hearth steel furnaces and tho use of wasto heat in rovcrberatory 
copper-melting furnaces is shown by Mathewson.® It is stated d that 
heat losses may bo reduced 40 per cent in open-hearth furnaces by 
the use of the waste gases. Peters e states that boilers of about 600 
horsepower are used between reverberatory copper-melting furnaces 
and the stacks, usually two boilers per furnaco being installed. By 
this method, when the furnaces are fired with soft coal, one-third 
the total heat value of the coal used is recovered as steam, tho tem¬ 
perature of gases being reduced from between 950° and 1,000° C. 
(1,730° to 1,S30° F.) to 350° C. (660° F.) by tho boilers. Douglas/ 
states that on reverberatory copper furnaces 45 to 55 per cent of the 
heat of tho fuel is recovered as steam, and that to this recovery is duo 
tho low cost of smelting attained. On oil-fired reverberatories prac¬ 
tically half as much steam is made by the wasto gases from a pound 
of oil after passing through the reverberatory as would bo made if the 
oil were burned directly under a boiler, the wasto gases being reduced 
from 1,150° C. (2,100° F.) to 400° C. (750° F.) It is also said* that 
some of these waste-heat boilers havo been in uso in copper furnaces 
for five years before being reset. 

a Stone, G. C. Note on utilization of waste heat of regeneraUve furnaces: Bull. 82, Am. Inst. Min. 
Eng., 1913, p. 2410. 

b Schreiber, J., Use of waste heat from the Siemens-Martin furnace: Stahl und Eisen, v«l. 33,1913, pp. 
45, 107. 

c Mathewson, E. P., Development of the reverberatory furnace for smelting copper ores: Proc. 8th Int. 
Cong. App. Chem., 1912, vol. 3, p. 133. 

d Anon., The use of waste heat on open-hearth furnaces: Iron Age, Feb. 20,1913; Eng. Mag., vol. 45, 
1913, p. 149. 

« Peters, E. D., Practice of copper smelting, 1911, pp. 314, 328, 329,139, 364. See also Sorenson, 8. S., 
Waste heat boilers in reverberatory furnace flues: Min. Sci. Press, vol. 107,1913, p. 575. 

/ Douglas, J., The relative importance of principles and practice in education: Met. Chem. Eng., vol. 
11,1913, p. 377. 

9 Mineral Industry, 1911, p. 216. 



ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 231 

Although the savings shown on brass furnaces might not be as 
great, they should be considerable. One firm states that it tried 
a hot-water coil for heating boiler feed water in one of the stacks 
from its natural-draft coke furnaces, but found that the coil inter¬ 
fered with the draft. Another firm that uses pit oil furnaces was 
designing a boiler, of the vertical type, for use with waste gases. 
This was to be in several sections, so that those sections normally 
taking the gases from any part of the battery that might not happen 
to be in use might be cut out of the circuit. The boilers were to be 
in series with the main boiler of the power plant and were expected 
to reduce the stack temperature to 300° F. The furnaces might be 
converted from oil furnaces to forced-draft coal furnaces at any 
time that fuel costs might make the change desirable and the boilers 
were expected to work equally well when the furnaces were run on 
either fuel. 

Another firm writes as follows: 

We have seven pit furnaces burning anthracite coal under forced draft. These are 
placed on either side of a 100-horpepower boiler, and the waste heat from the furnaces 
is led directly below the boiler. We can not estimate how much this eaves us in 
the way of fuel for the boiler; all we know is that we are using only 1$ tons of Poca¬ 
hontas coal per 10-hour run to obtain upward of 100 horsepower. We see an addi¬ 
tional advantage in disposing of the waste heat from the brass furnaces in this manner, 
in that the furnace tender’s occupation is rendered more bearable because of the 
comparatively small amount of heat above the brass furnaces. 

It is therefore seen to be quite possible to utilize by one or more 
of the above methods much of the waste heat from almost any type 
of furnace. The main precaution that has to be observed in the 
cases where the waste heat is used for other purposes than for pre¬ 
heating metal or the air for combustion is not to attempt to use 
the waste heat as the only sourco of heat when a constant heat is 
required and the furnaces are only intermittently used, or when 
close regulation of temperature is necessary. 

RECOVERY OF COAL OR COKE FROM ASIIES. 

If coal or coke furnaces can not be run so as to burn the fuel com¬ 
pletely, there is a possibility of recovering some of the unburned 
fuel from the ashes. In some plants visited so much unburned coal 
went through the grates that the ash pile was almost as black as 
the coal pile. 

Several plants report that the ash is roughly riddled and picked 
by hand, any good fuel, as well as any largo pieces of metal, being 
picked out, and that such hand picking is profitable. One plant 
finds that partly burned coal, owing to its freedom from moisture, 
can be satisfactorily used for the bed of the first heat in a pit furnace. 


232 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 

Peters ° states that of 114,000 pounds of soft coal used per 24-hour 
day per furnace in a big smelter, 26,000 pounds of coal and coke is 
recovered from the ash by jigging. The recovered fuel is briquetted 
and used. Recovery of combustible material from ashes by floata¬ 
tion in liquids of different specific gravities has also been suggested. 6 

USE OF BORINGS. 

There is a difference of opinion as to whether borings or other 
small pieces of clean metal produced in manufacturing operations 
within the plant should be used in the regular furnace charges, or 
should first be run into ingot, no fine material being used in the 
regular charges. 

The running of borings into ingot means an extra melting of the 
ingot before the metal can be run into castings, with consequent 
cost for fuel, labor, and lost metal. The majority of the manufac¬ 
turing plants reporting use from 15 to 25 per cent of their own borings 
in the regular charges, as is shown by the entries in the large table 
under tho heading “Composition of charge.” 

Some few jobbing foundries also use borings almost entirely, 
buying now metal for alloyed ingot only for castings that must meet 
exact chemical or physical specifications. 

When borings are used, much mechanical loss may result from 
carelessness in charging the borings. The bottom of tho crucible 
or furnace chamber is usually first charged with a small quantity 
of borings, gates and heavy scrap being placed on top of the borings 
and ingot metal on top of the gates. In open-flame furnaces the 
whole charge of borings may thus be put at tho bottom. In crucible 
furnaces part of the borings must be charged after the melt has 
been run down enough to leavo room in the crucible. The charging 
of borings, especially in too small crucibles, is often attended with 
much spilling of tho borings on tho floor and into the coke or coal 
space, or combustion chamber, of tho furnace outside the crucible. 
The spilling may bo somewhat avoided by care in charging, by sup¬ 
plying proper scoop shovels, and by using a sheet-iron funnel set 
into the top of the crucible. If the draft is strong, very light borings 
may be actually carried into tho flues and thus lost. The borings 
lie on top of the molten metal and unless continually poked down 
will lose some zinc even before melting, and if tho atmosphere is 
oxidizing will oxidize badly on account of their largo surface. 

For these reasons, coupled with the likelihood of borings of varying 
compositions being present, if care is not taken in tho machine shop 
to keep borings from different alloys separate, some of the larger 
plants consider that the best results are obtained by running the 


« Peters, E. D., Practice of copper smelting, 1911, p. 314. 

* Luller, A. F., Recovery of coke from ashes: Jour. Ind. Eng. Chem., vol. 5,1913, p. 425. 




ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 


233 


borings down into ingot in large furnaces, usually either reverbera¬ 
tory or open-flame. Each charge of ingot is then analyzed and 
the proper charge of boring ingot, new metals, gates, etc., deter¬ 
mined on the basis of their analyses. 

Some of the smaller foundries that do not wish to use borings in 
their regular work find it best to sell the borings to a refinery. 
Whether it is cheaper to ingot borings at the plant using them or 
to sell them will depend on the quantity of borings produced and 
the location of the plant. 

Oily borings should be treated in a centrifugal oil extractor in 
order to save the oil and to put the borings in better condition for 
being melted. 

BRIQUETTING OF BORINGS. 

If clean borings or similar fine material could be agglomerated 
into solid masses that would not fall apart on being charged and 
would sink beneath the surface of molten metal, it would seem 
that they should be melted with little, if any, more loss than occurs 
with ingot metal. In refining impure borings they are sometimes 
made into briquets, a binder, such as lime or pitch, being used to 
some extent, but briquets made of clean borings do not appear 
to have met with much success, the briquets disintegrating as soon 
as they become hot. Briquets made under such heavy pressure 
that the borings agglomerate without the use of a binder and become 
almost solid are now used. 0 The process has been developed mainly 
for use on iron, although its field should seemingly be much 
greater in connection with the more expensive nonferrous alloys. 
Briquetting has been tried in brass melting, b#t Reply 104 states 
that not enough saving in lost metal was effected over the charging 
of all the borings at the bottom of the furnace chamber to pay 
for the cost. For melting charges consisting entirely of borings, as 
in a refining plant, briquetting deserves at least a trial. 

Sperry b states that yellow-brass chips thus briquetted can be 
melted with a loss of only 1 V to 2 per cent, whereas without briquet¬ 
ting, the loss is at least 5 per cent. 

Wallace 0 reports an experiment in melting briquets of yellow-brass 
borings in which the melting loss was less than 3} per cent. 

Figures are given d showing that the loss on melting briquetted 
brass borings was 3 to 41 per cent, and on aluminum borings 15.3 per 
cent. It was stated that the loss on the aluminum borings would 

a Sperry, E. S., Briquetting borings: Brass World, vol. 7, 1911, p. 41; Chera. Abs., vol. 5, 1911, p. 1251; 
Woods, C. F., Report of oflicial chemist: Trans. Am. Inst. Metals, vol. 6,1912, p. 4; Metal Industry, vol. 10, 
1912, p. 405. 

b Sperry, E. S. (In discussion): Trans. Am. Inst. Metals, vol. 6,1912, p. 14. 

C Wallace, R. B. (In discussion): Trans. Am. Inst. Met., vol. 6,1912, p. 17. 

d Editorial, Briquetting machine for metal borings and turnings: Engineering (London), vol. 94,1912, 
p. 737; Jour. Inst. Met., vol. 9, 1913, p. 246. 



234 


HRASS-FURNACE PRACTICE IN THE UNITED STATES. 


have been about 50 per c?nt had the borings been melted without 
briquetting. 

RECOVERY OF METAL FROM WASTE MATERIALS. 

The recovery of metal from waste materials carrying considerable ' 
metal but too much other material to allow melting of the metal 
without a mechanical separation, or a refining melting somewhat 
along tiie lines of ore smelting, or both, is a problem that is receiving 
increasing attention in the most progressive plants. 

Such waste materials are shimmings—metal mixed with slag and 
oxide—usually the richest form of waste material from the foundry; 
spillings irom the ladles, which become mixed with molding sand; 
ashes from coal or coke furnaces into which metal has been spilled or 
dropped m ciiarging; dust from emery grinders and saws; dust, 
including some fiber, from polishing wheels; mud, containing abraded 
metal from tumbling barrels; and old crucibles. 

Some large plants retain a smelting and refining plant in connection 
with their regular work and get a large proportion of the metal they 
use out of wastes sold them by others. 

In one plant visited by the author the superintendent said that a 
3 mall neighboring foundry had been pa ving a cart man to carry away 
a pile oi slrimmings that had been accumulating for several months. 
The cartmo. sold the skimmings to a junk dealer for several hundred 
dollars. The junk dealer afterwards stated that he made a good 
profit as the material contained 60 per cent of metal. Such cases, 
happily, are rare. Many plants, however, closely approximate the 
case cited by sellings pile of skimmings at a lump sum without assay. 

In this connection Jones® makes the following pertinent remarks: 

There are a few objections that are raised in some quarters to disposing of scrap to the 
smelter. One is that the small dealer will call for scrap and haul it away without cost 
to the brass founder, while if he is situated at a distance from the smelter the freight 
charges may be high. This is offset by the greater net profit that is nearly always 
obtained when selling on an assay basis and by the smelter’s establishing local collect¬ 
ing points which thus eliminate the freight charges or reduce them materially. The 
small dealer has to pay cash against bill of lading, while in the past the smelters have 
delayed settlement until all assays have been completed. They are now willing, 
however, to pay three-quarters oi the estimated value of the shipment immediately 
after it is shipped and the remainder promptly on completion of the assay. 

Many brass founders are dubious about selling on an assay basis because they aro 
not familiar with the methods of sampling and assaying and the various calculations 
involved in arriving at the market value of scrap material. If they will devote a little 
time to the matter, they will find it is not such a formidable undertaking after all and 
that it will not require many assays to show them exactly what each grade of scrap 
• they produce is worth, provided, of course, that their manufacturing methods are 
standard and not subject to frequent changes. On account of the loose and unbusiness¬ 
like methods of selling that have prevailed in the past, there is su~o to bo a steady 


° Jones, J. L., The selling of brass-foundry refuse: Trans. Am. Brass Founders’ Assn., voL 4,1910, p. 63. 




ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 235 

increase in the number of those who dispose of their wastes on an assay basis. Even 
the firms that prefer the old methods are safeguarding themselves by having a sufficient 
number ot assays made on all waste products to indicate their value. If the market 
value oi c material is ascertained by having it assayed, competitive bids on it can then 
be better judged. 

Every brass founder will find it co his advantage to get in touch with one or more 
reliable smelters and become familiar with their methods of doing business on an assay 
basis. He should also have a competent metallurgical chemist examine his by¬ 
products and report on their average copper content and market value. 

The foregoing discussion deals with wastes of impure materials 
and those from which the larger pieces of metal have been removed. 
Material that is too line or contains too much foreign matter to allow 
its melting without undergoing a true smelting operation must of 
necessity find its way to the smelter. As such waste is considered 
only as copper-bearing material and is paid for only on the basis of 
copper content, it is evident that if the plant producing the waste 
would separate the larger pieces of metal, so far as they can be 
obtained free enough from other material to allow direct melting, 
such separation would pay, as the full metallic content, less the melt¬ 
ing loss, would be recovered instead of merely the wasted copper 
minus the smelting charge. 

A rough separation of metal from shimmings and, usually, from 
ashes may be economically made by most foundries, and by many of 
those whose output is smaller than the owners now consider will 
justify such a separation. 

METHODS USED FOR ROUOH SEPARATION OF WASTES. 

Out of 230 answers to the list of questions, 102 made no reply to 
the question referring to the use of a concentrating system for wastes, 
the inference being that the waste is sold without concentration of 
any sort. There were 32 replies stating definitely that the waste 
was sold. Three replies state that shimmings are charged bach 
with the next heat in order to free the entrained metal. Four 
replies state that the waste is hand piched, with or without rid¬ 
dling. One firm riddles and hand pichs the waste after it has 
been crushed. Two firms state that each form of waste is sold, but 
that the sweepings, shimmings, spillings, ashes, emery dust, etc., are 
each carefully hept separate, the richer waste not being mixed with 
the poorer, a practice that results in getting a better price for 
the waste than if all the wastes were indiscriminately mixed. 
One firm states that it is too small to attempt concentration, and 
another that it has no room for the necessary installation, but both 
agree that concentration is desirable for most plants. Five state that 
some concentrating system is in use, without describing it at all. 
Three report that they run regular refining furnaces on the wastes 


236 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 

(probably after some concentration). One washes the wastes by 
hand in the river. 

Most of the plants doing any concentration at all use merely a wet 
process, usually a ball mill with a stream of water running through it 
at such velocity tvs will carry off nearly everything but the larger 
pieces of metal. The overllow is run into a sump, and the tailings, 
after the water has soaked out, are either used for filling in waste 
ground, drawn away to a dump, or sold to smelters. Some firms 
report that the tailings are too low in copper content to be salable, 
although the separation is by no means complete. Others save only 
large pieces of metal by the process, the tailings being rather rich. 
One of these firms uses a tumbling barrel, charging the skimmings 
with the castings and running water through the barrel, the castings 
being used instead of balls to break up the slag. Four of these firms 
state that, although they use coke or coal furnaces and hence have 
ashes, skimmings and sweepings only are treated in the wet grinder, 
the ashes not being concentrated. One firm saves the waste and 
cleans it with a wet process once or twice a year. 

Twenty-three replies show a further step in concentration, the 
wastes being crushed by rolls, jaw crushers, stamps, edge runners, 
or ball mills, and the crushed material washed through sluice boxes 
or into jigs, and thence to vanners or Wilfley tables, or through various 
combinations of these. Three other firms use air separation. By 
air separation the firm represented in Reply 191, which uses open- 
flame oil furnaces, recovers as coarse metal from the skimmings 
0.83 per cent of the original charge by the use of a dry crusher, and 
a further 0.41 per cent of finer metal by exhaust-air separation. 
Another firm, using pit, coke, or coal furnaces, grinds all wastes in a 
ball mill through which a blast of air is blown. The heavy pieces 
of metal remain in the mill, and the fine metal, ash, etc., are blown 
through a large settling house, which catches some of the fine metal. 
Another firm first uses a wet ball mill for separating the large pieces. 
The tailings are then dried and ground fine without water; they 
are then dropped from a hopper down a pipe into a settling box. A 
blast of air enters one side of the settling box and carries off the lighter 
particles, the metal particles remaining in the box. 

Air separation is not used nearly as much as water separation, and 
the air method has been replaced by the water methods in several 
plants visited. In many of the more complete systems of water 
separation the water is run from the sump where the tailings are 
collected into a settling tank. The water is pumped over again by 
a centrifugal pump if water charges are high. 

One rolling mill uses a wet ball mill, the overflow passing through 
a Huntington mill, then to a vanner. It is estimated chat as much is 
recovered by the vanner as by the wet ball mills. One foundry uses 


ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 


237 


first a crushing barrel, passing the crushed material through a trommel 
with a water jet over it and then into a Hartz jig. Much of the ash, 
etc., is swept away before reaching the jig, the tailings from which 
contain 6 per cent of metallic oxides and 3 per cent of fine metal. 

One rolling mill first picks the wastes by hand to recover large 
chunks of metal and unburned fuel, then uses a jaw crusher, then a 
Huntington mill, and then Wilfley tables. Another mill uses edge 
runners for crushing and jigs for concentrating. Still another uses 
edge runners, followed by treatment in simple sluice boxes, the over¬ 
flow from which is carried to two Wilfley tables. The tailings from 
these contain only 0.25 per cent of copper, all of which is said to be 
in the form of oxide or silicate, and none metallic. This plant 
prefers edge runners for crushing, as they are thought not to crush 
the metal and to reduce the size of the metallic particles as much as 
ball mills, the stamp mills being considered particularly wasteful in 
this respect. Over half the recovery is made in the sluice boxes, 
and the metal there recovered is large enough and free enough from 
foreign material to go back to the furnaces. The metal recovered 
from the Wilfley tables is said to contain 30 to 35 per cent of copper, 
and, being thus impure and very fine, has to go to the smelter. 

The more complex installations of concentrating machinery are 
chiefly in large plants, such as rolling mills, which use pit, coal, or 
coke furnaces. One rolling-mill chemist stated that untreated 
ashes from rolling-mill pit furnaces havo an average copper content 
of 1 per cent; another put it at 0.5 per cent. 

Skimmings unmixcd with ashes usually give tailings from the wet 
grinders rich enough for sale to smelters. One firm using pit, oil 
furnaces, and crushing the skimmings in a wet ball mill reports 3 to 
5 per cent of copper in the tailings. 

Hughes, 0 in describing English practice, mentions that dry rid¬ 
dling and hand picking of all wastes, followed by wet grinding, is 
employed. 

Seipke, * * 6 in an article on German practice, in concentrating brass- 
foundry wastes, states that in Germany most foundries themselves 
recover the bulk of metal in largo enough pieces and sufficiently 
free from foreign material to allow its addition to ordinary charges, 
wet ball mills being used and having supplanted wet stamp mills. 
The tailings go to smelters or to the smelting departments of the 
large plants. They are made sufficiently fine by being put through 
dry screens and ball mills, from which some metal clean enough for 
crucible or reverberatory furnace melting is obtained. The recov¬ 
ered metal is run into.ingot. Then a pulp is mado with water and 

a Hughes, 0., Nonferrous metals in railway work: Jour. Inst. Metals, vol. 6,1911, p. 96; Metal Industry, 

vol. 9,1911, p. 463; Castings, vol. 9,1911, p. 13; Foundry, vol. 39,1911, p. 463. 

6 Seipke, F. W., Die Verhuttung Kupperhaltiger Industrieabfiille Metallurgie, vol. 9,1912, p. 121. 




238 


BRASS-FURNACE PRACTICE IN TIIE UNITED STATES. 


passed through sluice boxes to shaking tables, tho water being re¬ 
turned by centrifugal pump. The concentrate is then briquetted 
with lime and smelted in ? blast furnace tor its copper content. 

Apparatus for concentrating systems,® of a complexity varying 
with the class of wastes to bo handled and its amount, and espe¬ 
cially designed for use with brass, are on tho market. The apparatus 
vary from a set of crushing rolls, an elevator, a couple of jigs, and 
a centrifugal pump, for concentrating skimmings, dirty borings, 
etc., or some crushing device, a sluice, and a Wilfley or similar 
tablo for ashes, tumbling mud, emery dust, etc., to a system using 
both jigs and concentrating tables, and up to a complete and elab¬ 
orate installation such as is described by Wittich. 6 This consists of 
a revolving trommel, the coarse material from which goes to a picking 
belt for the recovery of unbumt fuel and large pieces of metal, and 
thence to a crusher, the fines going through a system of single jigs 
and dewatering cones which produce a concentrate of 25 to 30 per 
cent of metallic content. 7'he combined material then passes 
through crushing rolls and a screen to another system, embracing 
two-compartment jigs, and thence to concentrating tables. Tho 
wastes put through this carry 3 to 5 per cent of metal. 

The mechanical appliances used for crushing the waste and sepa¬ 
rating tho metal are rather similar to those used in tho crushing and 
concentrating of ores, which are described in considerable detail by 
Hofraan.® 

In the plant where the waste is produced, it is certainly advisable 
to collect all tho pieces of motal that are large enough to bo remelted 
readily and are without notablo admixture of foreign material, be¬ 
cause, besides the copper, the other constitutents of the alloys are 
thus recovered. The recovery seems to bo best accomplished by the 
use of some crushing apparatus, a wet ball mill for example, fol¬ 
lowed by a jig, or, at least, sluice boxes. 

Tho tailings from such a recovery, containing about half the 
original metallic content of the waste, have to go to tho smelter. 
Whether it will pay to eoncentrate the tailings in the plant pro¬ 
ducing them depends on tho quantity of such material and the loca¬ 
tion of the plant producing it. In some localities, the tailings from 
small foundries using a fuel that produces no ashes, so that skimmings, 
sweepings, and grindings make up most of the waste, will probably be 
rich enough to warrant selling them without concentration, inas¬ 
much as their quantity may not bo enough to justify the installation 
of separating tables, or vanners. 

a Anon., Concentration of brass-foundry wastes: Foundry, vol. 140,1912, pp. 9fi, 495. 

f> Wlttlch, L. L., Recovering brass from foundry cinders: Eng. and Min. Jour., vol. 95, 1913, p. 853; 
Jour. Ind. Eng. Chem., vol. 5,1913, p. 512. 

< Holman, II. O., General metallurgy, 1913, p. 534, et seq. 



ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 


239 


In plants having ashes the situation is different. Their tailings 
are bulky and of a low copper content. Also the value at the smelter 
of a pound of copper in copper-bearing material is much less when 
mixed with, say, 99 pounds of ash, than when mixed with, say, 40 to 
GO pounds of ash. As freight charges to a distant smelter on low- 
grade material are high per pound of copper contained therein, and as 
the copper-bearing material is at one time flowing out of the jig or 
sluice boxes ready to go on a separating table or vanner, it is prob¬ 
able that most ash-producing foundries, even though they ma} r run 
onlv half a dozen furnaces and use the concentrating table or vanners 
only a few times a year, will find that it will be to their advantage 
to effect the separation of the smaller particles of metal before selling 
the low-grade tailings. 

Local conditions may operate against such separation, but it is 
certain that a more general use of separating tables or vanners than 
is made at present would be advantageous. Several cases have been 
noted in which the use of Wilfley tables or similar separating devices 
on low-grade waste, too poor to bear shipment to the smelter, has 
paid extremely well. Their use is the rule rather than the exception 
in rolling mills. 

Parsons a cites a plant in which one experimental Wilfley table 
saved $80 a day. One foundry visited had recently installed tables 
and was working up at a handsome profit a large pile of sweepings 
that was too low in metallic content to warrant freight charges to 
the nearest smelter and would have required carting away at con¬ 
siderable cost had the table not been put in. Another plant visited 
had in previous years made merely a rough separation by crushing 
and washing. The tailings, too poor for salo to a smelter, had been 
drawn out in the yard. After the more complete concentrating sys¬ 
tem had been installed excavation for a new building was begun in 
the yard, and on trial the excavated material was found to contain 
enough metal to pay many times over for its concentration; hence 
the yard is being worked as a brass mine. Neither of these plants 
has any ashes to contend with, yet tables are found valuable. 

Reply 16 (subdivision 1 of the large table) cites an example of a 
good recovery made with a complete concentrating system. The 
gross melting loss is given as 3 per cent and the net loss as 0.5 to 0.G 
oer cent. The 3 per cent figure for the gross loss is common, but 
such good recovery is not shown by plants with a less complete 
system. The rolling mills’ figures in the table in general show a good 
recovery, owing to the use of complete recovery systems. 

Refuse from the exhaust of polishing wheels and sweepings from 
wooden floors containing splinters, or any waste containing much 


a Parsons, C. L., Discussion in mineral wastes symposium: Jour. Ind. Eng. Chom., vol. 4,1911,p. 155. 




240 BRASS*FURNACE PRACTICE IN THE UNITED STATES. 


combustible material, may be purified by burning the combustible 
material in mulllo furnaces ° and subjecting the residue to wet 
concentration. 

Sperry 6 decries wet washing of skimmings, claiming that all the 
oxides and fine metal are lost, and recommends that they be merely 
riddled through a 20-mesh riddle, that what goes through be saved 
(crushing is not mentioned, but must be involved to get the material 
to such fineness), and that what remains on the screen bo picked by 
hand. This recommendation is evidently based on a comparison 
with a mere rough separation, without the uso of tables. Hand 
picking of all metal larger than a 20-mesh fineness would seem a 
more laborious process than wet washing of the material left on the 
screen. If the proportion of oxide is high, dry riddling might be 
advisable, the fines going to the smelter for recovery of metal from 
the oxide and the rest being put through a concentration process, 
including Wilfley tables. 

In a discussion on the treatment of the refuse in brass and copper 
mills Spittle c advocates keeping various forms of waste separate, 
whether they bo concentrated in the plant itself or at a smelter. 
Earle did not consider that it paid a manufacturer to recover his 
own waste. Johnstone advocated putting ashes through a cupola or 
blast furnace without concentration. This view Was strongly com¬ 
batted by Sheppard, who said that such a procedure would cause the 
loss of all the zinc, and by Spittle, who said the raw ashes would 
choke the furnace and that wet concentration before smelting was 
preferable. 

One firm describes their cupola-refining process as follows: 

In our practice we make daily a large quantity of brass-foundry refuse which is 
composed of coke ashes, slag shimmings taken from our furnaces preparatory to pour¬ 
ing, fine emery-wheel grindings made in dressing castings, and fire-brick linings of 
all of our furnaces, all of which contain brass in different forms. 

This is the material that we are charging into the cupola furnace. The furnace is 
36 inches in diameter and contains a sand bottom 7 inches deep. On top of this there 
is a 9-incli cupola brick lining, and above this is a 4-inch water jacket. Into this we 
keep charging various ingredients as follows, the figures being approximate: 


Ingredients: Pounds. 

Coke. 120 

Limestone. 60 

Rolling-mill cinders. 15 

Foundry refuse. 400 


We put the cupola into operation once a week for about two days, and we recover 
from it 600 pounds of metal and 600 pounds of slag per hour. Therefore, our total 
charge of refuse is about 2,000 pounds per hour, of which we recover GOO pounds of 

o Sperry, E. 8., Questions and answers: Brass World, vol. 9,1913, p. 182; vol. 7,1911, p. 54. 
t> Sperry, E. 8., The treatment of skimmings in small brass foundries: Brass World, vol. 9,1913, p. 39. 
c Proceeding*: of meeting of Birmingham section of Institute of Metals (British), Dec. 10, 1912: Brass 
World, vol. 9,1913, p. 49. 








ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 


241 


metal, or 30 per cent. It is operated with an air pressure of 12 ounces, using a blower 
operating at 240 revolutions per minute and supplying 8 cubic feet of air per revolu¬ 
tion. The coke we use is 72-hour Connellsville. 

The bottom lining of sand and the brick lining are replaced after each two days’ run 
of 24 hours each. However, it would not be necessary to reline this so often if the 
furnace were kept in continual operation, as it probably would run for 6 days of 24 
hours each. 

The brass that we recover from this operation runs 74 to 78 per cent copper, 5 to 8 
per cent tin, 4 to 6 per cent zinc, trace of iron, and balance lead, according to kind 
of material that we have been costing. 

As a 30 per cent recovery is made from the refuse charge, it is evi¬ 
dent that a preliminary concentration is made, although tills was 
not mentioned. 

A necessary part of the concentrating equipment is a magnetic 
separator for removing iron. The concentrated metal is usually 
dried in pans over steam coils or in ovens. The drying may be done 
by waste heat. 

When the metal recovered by concentration is not too fine and is 
not too heavily loaded with foreign matter, it may be run into ingot 
instead of smelted for the mere copper content. 

Fluxes advocated for the removal of foreign matter in such metal 
are glass,® sodium carbonate mixed with sand or lime , b lime, and 
fluorspar, and plaster of Paris. c 

Concentrates high in impurities should probably be sent to the 
smelter, as one authority d advocates doing, but only, he advises, 
after a preliminary concentration. 

The smelting of such material in the electric furnace without much 
metal loss and the recovery of other metals as well as the copper is an 
interesting possibility, and is said to have been done experiment ally . e 

One plant visited keeps all wastes from different alloys separate. 
Red brass, manganese bronze, and aluminum are the main alloys 
melted, and several separate receptacles for the shimmings are pro¬ 
vided in convenient places, those for red-brass shimmings being 
painted red, those for manganese bronze yellow, and those for 
aluminum, with aluminum paint. 

In some foundries, particularly those doing small bench work and 
using small flasks with end pouring, the flasks are set on spill troughs, 
which catch any spillings, or metal lost by run-outs, thus preventing 
much of the admixture of sand otherwise occurring. 

Two firms reported good results from putting the shimmings from one 
melt back into the next melt of the same alloy, one firm stating that 

a Lewis, E. A., The selection and use of scrap: Metal Ind., vol. 10, 1912, p. 22. 
b Krom, L. J., Fluxes from the viewpoint of a metallurgist: Metal Ind., vol. 8, 1910, p. 205. 
c Krom, L. J., op. cit., p. 204; Sperry, E. S., Fluxes as applied to the brass foundry: Trans. Am. Brass 
Founders' Assn., vol. 4, 1910, p. 74. 
d Editorial, Economics of the future; Metal Ind., vol. 10, 1912, p. 468. 

• Editorial, Tho electric furnace and the scrap-metal business: Met. Chem. Eng., vol. 9, 1911, p. 621. 

44712°—Bull. 73—16-16 






242 brass-furnace practice in the united states. 

tlu* gross shrinkage during a month in which this was done was 50 per 
cent less than in a month in which it was not done, and that although 
the net recovery might not be very different, it cut down the quantity 
of waste that had to be concentrated. 

One rolling mill (Reply 151, subdivision 10 of the large table), 
using only a wet ball mill and no tables or jigs for recovery, reported 
that, by care in charging, only 0.15 per cent of the melt got into the 
ash, or only 0.06 per cent when their best furnace tender’s work alone 
was considered. As not all the furnace tenders were so careful, the 
proportion of the gross melt recovered from ashes, spillings, etc., 
was 0.50 per cent. This firm skims the charcoal, salt flux, and dross 
into a tank of water, later drying out the charcoal and dross, riddling 
the material, and putting the charcoal back into the pots. The firm 
claims that this process effects a great saving. The loss figures are 
not accurately kept, and if the estimates of this firm on their loss 
(3 per cent gross and 24 per cent net) are correct, their volatilization 
loss must be high, as the figures are rather above the rolling-mill 
average. A representative of the firms says that the estimate that 
7.500 pounds of zinc is lost daily through the stacks of Waterbury 
alone ° was high, but stated that the metal losses in the rolling-mill 
business were equal to more in money than the profits from the mills. 

Skimming into water is generally thought to involve a saving, 
as it breaks up the slag and allows clean globules of metal to separate. 
Many plants, however, fear to do this, and in one plant a caster 
was killed by the explosion of a skimming tank due to the breaking 
of a pot in such a way that a large quantity of molten metal fell into 
the tank. * 6 However, these tanks are usually covered, save for a 
small opening in which to skim, a precaution that minimizes, although 
it does not entirely eliminate, the danger cited. 

The dropping of a little molten metal into a large volume of water 
is not dangerous, although the running of a large quantity of metal 
into a pool of water or the addition of damp metal to a pot of molten 
metal is. However, as accidents like the one cited are possible, 
skimming into water must be classed as dangerous. 

RECOVERY OF ZINC OXIDE. 

The recovery of zinc oxide from flue dust is often suggested. 
Iliorns c prescribes a siphon-shaped flue that carries the waste gases 
over running water. The water vapor is said to precipitate the zinc 
oxide. In literature relating to patents other forms of the same 
device appear as accessories to some types of furnaces. 


a Parsons, C. L., Notes on mineral wastes: Bull. 47, Bureau of Mines, 1912, p. 21. 

6 Editorial: Metal Ind., vol. 8, 1910, pp. 48, 172. 

« Iliorns, A. U., Mixed metals, 1910, p. 136. 



ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 


243 


Krom ° records that by allowing settling space in the main flue 
and chimney one concern recovered 80,000 pounds of salable zinc 
oxide. The stack was pulling on 80 pit furnaces, probably coal-fired- 

One reply to the list of questions states that chimney dust is sold 
to the smelter, but the smelter is probably a copper smelter, the 
copper only being recovered from particles of brass mechanically 
carried along by the draft. 

The recovery of zinc oxide in connection with the smelting of 
brass refuse has also been suggested, 6 the recovery being made along 
lines similar to cupola melting, the zinc fumes being run through a 
bag house. 

Price c states that with coal melting, the zinc oxide is too much 
contaminated by dust and ashes to make its recovery feasible, but is 
of the opinion that the zinc oxide from furnaces fired with producer 
gas or oil would be pure enough to warrant recovery. Parsons d 
concludes that with gas or oil firing the recovery of zinc oxide by a 
proper method would be feasible. 

One plant visited reported that a wet method of catching the flue 
dust from its oil furnaces had been tried, but that the product was 
not salable. However, the recovery was from an alloy containing 
only 15 to 20 per cent of zinc. Flue dust from yellow brass would 
produce a purer oxide. As Krom e has reported the recovery of 
salable oxides by the mere use of settling chambers, the application 
of electrostatic precipitation, such as in the Cottrell process, to brass- 
furnace flue dust is worth considering. Bassett f classes the method 
as a possible solution of the problem. As it works successfully on 
smelter fume, cement dust, smoke, etc., o there is no doubt but 
that it would effect a practically complete recovery of the zinc oxide. 
If no means can be found effectively to prevent the volatilization 
of zinc, the recovered zinc oxide might be worth enough to justify 
the installation of the Cottrell process in large rolling mills making 
yellow brass, but as zinc is worth more in the molten furnace charge 
than as an impure oxide, prevention is even more desirable than 
precipitation. 

a Krom, L. J., Development of melting furnaces: Metal Ind., vol. 7, 1909, p. 289. 

b Sperry, E. S., Saving the zinc as well as copper in brass refuse: Brass World, vol. 9, 1913, p. 208. 

c Price, W. B., Discussion in mineral wastes symposium: Jour. Ind. Eng. Chem., vol. 4, 1912, p. 166. 

d Parsons, C. L., loc. cit. 

« Krom, L. J., loc. cit. 

/ Bassett, W. II., Zinc losses: Jour. Ind. Eng. Chem., vol. 4,1912, p. 164. 

a Cottrell, F. G., Electrostatic precipitation of suspended particles: Jour. Ind. Eng. Chem., vol. 3, 1911, 
p. 542; Dust precipitation by electrostatic means: Met. Chem. Eng., vol. 10, 1912, p. 172; Mineral losses in 
gases and fumes: Jour. Ind. Eng. Chem., vol. 4,1912, p. 182; Schundt, W. A., Control of dust in Portland 
cement manufacture by the Cottrell precipitation process: Proc. 8th. Int. Cong. App. Chem., 1912, vol. 5, 
p. 117; Jour. Ind. Eng. Chem., vol. 4,1912, p. 718; Met. Chem. Eng., vol. 10,1912, p. 611; Bradley, L., Elec¬ 
trical precipitation of suspended particles by the Cottrell process: Proc. 8th Int. Cong. App. Chem., 1912, 
vol. 26, p. 471; Met. Chem. Eng., vol. 10,1912, p. 686; Jour. Ind. Eng. Chem., vol. 4, 1912, p. 908; Strong, 
W. W., Electrical precipitation of carbon smoke: Proc. 8th Int. Cong. App. Chem., 1912, vol. 25, p. 617; 
Pietrusky, K., Das Cottrellsche Verfahren: Zeitschr. angew. Chem., vol. 25,1912, p. 2107. 



244 


BRASS-FURNACE PRACTICE IN T11E UNITED STATES. 


STANDARDIZATION OF ALLOYS. 

One of the greatest wastes in the brass industry comes from using 
too expensive an alloy when a less expensive one would answer, or 
from using too cheap an alloy when the physical properties of a more 
expensive alloy are needed. When any nonferrous alloy is to be 
used for any given purpose, there are certain physical properties, 
such as tensile strength, ductility, frictional qualities, and resistance 
to corrosion, that are required. The cheapest alloys that will give 
these qualities with a reasonable factor of safety are the best. Too 
often, however, a firm buying from a jobbing foundry, or the manu¬ 
facturing department of a plant ordering material from its own 
foundry, will specify an expensive valve metal, when all that is really 
needed for the work in hand is an alloy of only moderate strength 
with fair resistance to corrosion; that is, a yellow or red “antirust 
metal ,” as it might be called. A more rational way is to determine 
by experiment the physical properties that are required, and to use 
the cheapest composition that will meet them. 

If specifications are not made, there is often a tendency on the part 
of the foundry to supply an alloy that is not of high enough grade 
to give good service in the use to which it is to be put. On the other 
hand, instead of finding out what properties are really required, a 
clerk or a foreman will decide to use on a given order some one of the 
regular mixtures used in the foundry concerned, without thinking 
whether the alloy is expensive or cheap. 

The number of different alloys in the mixture book of the average 
jobbing foundry and, to a slightly less degree, of most manufacturing 
plants, is appalling, and it is a difficult task to take care of the gates 
and scrap from the various alloys without getting them mixed. The 
jobbing foundry often has to meet specifications from different cus¬ 
tomers for alloys that differ slightly, but are to be used for the same 
purpose, and is thus compelled to handle a much larger number of 
alloys than are really necessary. Moreover, when a more expensive 
alloy is used than is needed, the cost is high. With copper at, say 15 
cents a pound, zinc and lead at approximately 5 cents a pound each, 
and tin at about 50 cents a pound, 0.5 per cent of copper that might 
as well be substituted by lead or zinc means an unnecessary cost 
for the alloy of 10 cents per hundredweight. If 0.5 per cent of tin 
could be replaced by copper, the saving would be 35 cents per hun¬ 
dredweight, and if by zinc or lead, 45 cents. Hence the problem is 
most important, and authoritative determination of the properties 
of alloys required for particular uses, and of the cheapest composition 
that will give those properties, is most desirable. 

Tho Society of Automobile Engineers, through its standards com¬ 
mittee, is doing a good work in drafting standard specifications for 
the nonferrous alloys suitable for automobile construction. 


ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 245 

The need for such specifications is clearly shown by the various 
mixtures reported as used by the firms replying to the list of questions 
sent out. No special attempt was made to obtain figures as to the 
exact composition of the alloys used, the questions being designed 
to obtain information as to the melting practice on red brass and 
on yellow brass, or manganese bronze, in order that the data might 
he roughly separated for alloys high and low in zinc. However, in 
some instances the composition of a few of the alloys mostly used 
in the plants replying was given, although the majority of replies 
were on the basis of red or yellow brass. The list following has been 
compiled from the data furnished as to the composition of various 
alloys. The content of phosphorus, aluminum, or other deoxidizer 
has been disregarded, and the figures are accurate within 0.5 per cent. 


Composition of some alloys used in brass foundries. 
ALLOYS OF COPPER AND TIN. 


Material. 

Copper. 

Tin. 

Zinc. 

Lead. 

Bell metal. 

Per cent. 
83$ 
86 

88 

89 

90 

Per cent. 

14 

12 

11 

10 

Per cent. 

Per cent. 

Do. 



Gear bronze. 



Do. 



Do. 







ALLOYS OF COPPER, ZINC, AND TIN. 


Tobin bronze. 

61 

1 

38 


Naval brass. 

63 

1$ 

35$ 


Do. 

73 

2 

25 


Do. 

85 

7$ 

74 


Gear bronze. 

86 

13 

i 


Gun metal o. 

88 

10 

2 


Do. 

90 

7 

3 


Do. 

91 

8 

1 








ALLOYS OF COPPER, TIN, AND LEAD. 


Leaded bronze, chiefly for bearings 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 


76 

9 


15 

80 

12 


8 

80 

10 


10 

80$ 

9 


10$ 

82 

16 


2 

84 

6 


10 

87 

11 


2 

90 

7 


3 


ALLOYS OF COPPER, ZINC, AND LEAD. 


<1 brass . 

83 


12$ 

18 

4$ 

2 


80 



80 


16 

4 


80 


15 

5 


72 


26 

2 


70 


26 

4 


70 


24 

6 

ollow brass . 

67 


30 

3 


67 


29 

4 


67 


27 

6 


66 


32$ 

1$ 


65 


34 

1 


65 


30 

5 


64 


32 

4 


62 


34 

4 


60 


35 

5 



■ 




« Government composition. 













































































































246 BHASS-FURXACE PRACTICE IN THE UNITED STATES. 

Composition of some alloys used in brass foundries —Continued. 

ALLOYS OF COPPER,ZINC, TIN, AND LEAD. 


Material. 

Copper. 

Tin. 

Zinc. 

I>ead. 


Per cent. 

Per cent. 

Per cent. 

Per cent. 

Leaded gun metal and leaded bronie. 

75 

9 

1 

15 

I)o. 

77$ 

6$ 

5$ 

104 

Do. 

SO 

7$ 

1 

Ilf 

Do. 

80 

9 

3 

8 

Do. 

81 

6$ 

1$ 

11 

Do. 

85 

11 

1 

3 

Do. 

87$ 

10 

1$ 

1 

Do. 

87$ 

10 

2 

$ 

Do. 

88 

9 

2 

1 

Do. 

88 

8 

3 

1 

Do. 

88$ 

7 

2$ 

2 

Do. 

90 

8 

1 

1 

Do. 

91 

7 

1 

1 

Do. 

91$ 

6 

1$ 

1 

Half yellow and half red metal. 

70 

6 

20 S 

4 

Do. 

72 

6 

15 

m 

4 

Do. 

73 

2 

22 

3 

Do. 

73 

3 

21 

3 

Do. 

75 

5 

15 

5 

Do. 

75 

10 

10 

5 

Do. 

754 

1$ 

16 

7 

Do. 

76 

1 

22 

1 

Do. 

76 

1 

20 

3 

Do. 

76 

3 

18 

3 

Do. 

78$ 

3$ 

14 

4 

Do. 

78 

5 

16 

1 

Do. 

78 

3 

14 

5 

Do. 

78 

3 

12 

7 

Do. 

79 

3 

9 

9 

Do. 

SO 

1 

17 

2 

Do. 

81 

2$ 

16 


Ordinary red brass or composition a . 

80 

5 

10 

5* 

Do. 

80 

6 

8 

6 

Do. 

80 

7 

8 

5 

Do. 

SO 

6 

7 

7 

Do. 

80 

4 

7 

9 

Do. 

SO 

9 

6 

5 

Do. 

SO 

8 

4 

8 

Do. 

81 

6 

8 

5 

Do. 

82 

6 

11 

1 

Do. 

82 

6 

6 

6 

Do. 

S2 

4 

9 

5 

Do. 

82$ 

4 

10$ 

3 

Do. 

83 

4 

7 

6 

Do. 

83 

6 

6 

6 

Do. 

83$ 

4$ 

8 

4 

Do. 

84 


8 

6 

Do. 

84 

5 

6 

5 

Do. 

84 

4 

6 

6 

Do. 

84 

7 

6 

3 

Do. 

84 

3 

10 

3 

Do. 

85 

5 

6 

4 

Do. 

85 

6 

6 

3 

Do. 

b 85 

b 5 

b 5 

b 5 

Do. 

85 

6 

5 

4 

Do. 

85 

6 

4 

5 

Do. 

85 

64 

4$ 

4 

Do. 

86 

2 

7 

4 

Do. 

86 

5 

6 

3 

Do. 

87 

3$ 

7 

24 

Do. 

87 

2 

7 

4 

Do. 

87 

3$ 

6$ 

3 

Do. 

87 

5 

5 

3 

Do. 

87 

4$ 

4$ 

44 

Do. 

87$ 

5$ 

5$ 

1$ 

Do. 

88 

2 

W 1 

9 


Do. 

88 

3 

8 

4 

Do. 

88 

5$ 

4 

24 

Do. 

88 

5 

3 

4 

Do. 

89 

3| 

31 

31 

Do. 

91 

2$ 

2$ 

4 




*1 



° Used for valve metals, hard brasses, steam metals, etc. 
b One of the most common compositions. 



















































































ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 247 

Tho list does not include the various alloys of nickel, such as Ger¬ 
man silver and monel metal, nor the various types of manganese 
bronze. One firm sent in its mixture sheet with the request that 
tho composition of the alloys be not published. Had these been in¬ 
cluded, 10 more would have been added to the list of alloys of copper, 
zinc, tin, and lead only. It is not an uncommon thing for a foundry 
to have from 20 to 40 different alloys of copper, zinc, tin, and lead 
on the list of alloys that they cast. Tho full list of rolling-mill alloys, 
none of which is included here, would also be a long one . a 

It is, of course, conceivable that 40 alloys in a single foundry, or 
the list of 100 cited above in the foundry industry, is warranted, and 
that each has its particular use. However, it is certain that each of 
the nine different compositions of cast yellow brass shown in the 
table can not bo the cheapest that would serve for the use to which 
such brass is put. It is also certain that, even if the value of the scrap 
of the more expensive alloys is as much more than that of the cheaper 
alloys as the composition w'ould indicate, a doubtful relation judging 
from the usual methods of sale and use of scrap, some firms are un¬ 
necessarily tying up good money in the extra cost of a more expensive 
alloy than is needed. 

Another cause of waste is the weighing of small quantities of 
expensive metals, such as tin, on large scales not sufficiently delicate 
for the purpose, a method by which it is easy to add to a small pot 
of metal a half or a quarter of a pound more of tin than is required by 
the formula. On the other hand, too little tin may be added to give 
the desired properties. Small, accurate scales only should be used 
for weighing small quantities of metal. One foundry visited uses a 
decimal system in all its weighing. The pound is still the unit, but 
the scales read in pounds and tenths of a pound, the word “ounce” 
not being used in the foundry. This arrangement means a great 
deal less w r ork in calculating furnace charges. 

The metallurgist of one rolling mill called attention to the w T aste 
occasioned in the remelting, in rolling mills, of copper for casting 
rolling ingots, as many of the standard sizes of ingots might as well 
be cast direct from the refining furnace in the smelter and sold to 
the rolling mills ready to be rolled instead of in ordinary ingot form. 

EMPLOYMENT OF A METALLURGIST. 

The best w^ay to make sure that the proper alloy is chosen for a 
particular purpose, and after the composition of the alloy has been 
selected, that the proportions of the components are maintained within 
working limits, is to have a competent metallurgical chemist or metal- 

a See editorial. Economies of the future: Metal Ind., vol. 10, 1912, p. 46S; Krom.L. J., Manufacture of 
wrought brass: Metal Ind., vol. 8, 1910, p. 8. 



248 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


lurgical engineer, whose business it is to fit an alloy to the desired prop¬ 
erties in the cheapest way, to vary the alloy to get a cheaper alloy 
with the same properties as the metal market changes, to make up 
the mixtures in accordance with the quantity and the analysis of the 
scrap that is to be used, and to supervise the melting process as well. 
Also under the supervision of a metallurgist come the examination of 
such material as new metals, scrap metals, composition ingot, mold¬ 
ing sand, core sand, core binders, lluxes, fuels of all sorts, etc., which 
should either be bought under specifications or analyzed or tested 
for their suitability for foundry use; physical testing of the alloys 
produced; efficiency tests of furnaces and methods of furnace opera¬ 
tion; control of metal mixtures, furnace operation, core mixtures, 
core-oven operation, and core testing; determination of the proper 
baking temperatures for cores; and operation of the ovens under 
pyrometric control. 

If no metallurgist is employed, it is a step in advance to have an 
analyst to determine the composition of such alloys as may be sub¬ 
mitted to him, but to obtain the fullest benefit from chemical work 
there should be chemical control of the mixtures as well. A mere 
analyst who is not able or not allowed to control the mixtures and 
the melting can not help his firm to anything like the degree that a 
metallurgist, using his chemical knowledge in supervision of the 
melting room, can. As Bragg® puts it, “the laboratory with a 
1 chemist’ is not worth nearly so much as a chemical engineer who 
has a laboratory.” 

The metallurgist is usually the best man to maintain, as well as to 
establish, on the basis of his tests, the standards for melting speed, 
fuel consumption, and metal loss in the furnaces used, and he is the best 
fitted one for finding out and eliminating the causes of foundry and 
mill defects in the metal. Metallurgists are not only becoming more 
common in brass foundries and rolling mills, but, in plants where their 
activities were formerly confined solely to the laboratory, are being 
given fuller charge of the practical matters with which they are 
especially fitted to deal. It is almost as common to see advertise¬ 
ments stating that the nonferrous alloys produced by the advertiser 
are made under the control of skilled metallurgists as it is to see a 
similar statement of chemical control in the advertisements of 
automobile tires. 

Primrose 6 reflects the English attitude in the paragraphs following: 

For the accurate control of a brass foundry, it is essential to have a well-equipped 
metallurgical and testing department, especially when the products have to conform 
closely to specification. Accurate knowledge of the allowances to be made in melting 
must be ascertained, and the amount of oxidation and volatilization losses under the 
particular conditions of working must be determined in order to maintain a uniform 


® Bragg, C. T., The chemical engineer in the brass foundry: Metal Ind., vol. 8,1910, p. 64. 

* Primrose, U. 8., A discussion of modern brass founding: Foundry, vol. 40, 1912, p. 366. 







ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 


249 


composition of the resulting alloys. All scrap metal bought should be melted, cast 
into ingot, and stacked in lots according to its analyses. The best results are obtain¬ 
able only by making up the proportions of the charge constituent from the laboratory 
analysis, and in order to keep a thorough check on the resulting melts it is advisable 
to have these analyzed also. All raw material, such as copper, tin, zinc, scrap, etc., 
should be bought to analysis and carefully checked on delivery to insure that it con¬ 
forms to specification. Where it is not possible to purchase on this basis the material 
ought to be carefully analyzed, and mixed accordingly. 

The cost price of an alloy is largely determined by the price of the component parts, 
and when these differ considerably in value, even a slight variation in the alloy com¬ 
position increases its cost. A wide variation may quite easily occur in practice which 
is not controlled by chemical analysis, so that the cost of chemical control soon pays 
for itself several times over. 

It is well known that the German attitude is similar. 

The coming American attitude is reflected by a recent editorial a 
which says: 

The continual advance of metallurgical knowledge will lead in the near future to a 
complete change in the method of brass manufacture. * * * Works which are 
now employing their own chemists, and by chemist we mean a professional man, 
not a rule-of-thumb tester, find that they can not do without him and he is becoming 
more and more useful in the foundry and rolling mill. The sneers of a few years ago, 
when so-called practical men laughed at the idea of a chemist in a brass mill or foundry, 
are things of the past. It is a wonder that the trade has existed so long without a 
chemist. It is a sign of progress when firms advertise for a metallurgist to take charge 
not only of their laboratory but also their foundry. 

Sperry b says: 

To-day, the chemist is as much a need in the brass business as the actual casters or 
melters themselves, and his employment has changed the industry from one of the 
“rule of thumb ” to one conducted upon a scientific basis. 

APPLYING SCIENTIFIC MANAGEMENT TO FURNACE PRACTICE. 

The brass-foundry and rolling-mill industry is taking a great 
interest in the recent industrial development known as scientific 
management, as is evidenced by the fact that both the American 
Institute of Metals and the American Foundrymen’s Association 
had papers on the subject at their joint meeting in 1913. c 

Although the books and papers of the leaders of the movement 
deal mostly with efficiency in its larger application to industry in 
general , 1d to some specific industry as machine-shop practice,® or 

a Economics of the future: Metal Ind., vol. 10, 1912, p. 467. 

b Sperry, E. S., What the chemist has done for the brass industry: Brass world, vol. 9,1913. p. 343. 

c The titles of the papers before the American Institute of Metals were as follows: The efficiency engineer 
in tho foundry, by E. A. Barnes; IIow scientific management worked in our plant, by C. B. Bohn; Prepa¬ 
ration for scientific management in our plant, by W. M. Corse; Core room economics, by O. F. Flumerfelt. 
The titlesof tho papers before the American Foundrymen’s Association were as follows: How to make a time 
study (also read before the Am. Inst. Met.), by C. E. Knoeppel; Put your house in order, by F. A. Park- 
hurst. These papers will appear in the 1913 transactions of the two societies. 

d Taylor, F. W., Shop management: Trans. Am. Soc. Mech. Eng., vol. 24, 1903, p. 1; The principles of 
scientific management, 1911; Emerson, H., Efficiency as a basis for operation and wages, 1912; Twelve 
principles of efficiency, 1912; Gantt, II. L., Work, wages, and profits, 1911. 

t Parkhurst, I'. A., Applied methods of scientific management, 1912; Gilbreth, F. B., Concrete system, 
1908; Brick-laying system, 1909. 



250 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 

to foundries in a general way,® there is no published account dealing 
in any detail with its application to brass-furnace practice. 

As all authorities on scientific management, although differing 
in detail, agree on certain principles of operation of any industrial 
plant, and as those principles, as indicated by a study of the furnace 
data collected in this investigation, may profitably be applied to 
furnace operation for the elimination of waste, it is easiest to sum up 
the basic principles of the proper operation of brass furnaces by 
using some of the phraseology of scientific management. 

The use of the term “management” as applied to the operation of 
brass furnaces gives the correct point of view in two ways—it serves 
to emphasize the fact that the operation of a furnace is as important as 
the type of furnace designed or the fuel used, and it places the respon¬ 
sibility for preventable waste on the shoulders of the management, 
instead of on an inanimate furnace, or a possibly illiterate furnace 
tender. 

Under any form of management that may fairly be called scientific, 
some of the vital details are: Proper choice of equipment; standards 
based on actual scientific tests; maintenance of standards; and accu¬ 
rate and adequate records as a means of maintaining standards. . 

PROPER CHOICE OF FURNACES. 

In choosing a brass furnace, the selection should be made with 
reference to the alloys to be melted, their liability to volatilize, the 
quality of metal desired as regards freedom from oxidation and gas 
absorption, the quantity of molten metal to be produced, and the 
cost of the various possible fuels in a given locality. For some 
alloys, the whole range of furnace types might give the quality of 
metal desired, but certain types of furnaces might be barred by 
their lack of speed, and other types by the cost of fuel. For other 
alloys, the volatility of zinc might eliminate some furnace types; or 
the necessity for large production might be absent, so that a relatively 
slow furnace would serve, and the fuel cost might then be the decid¬ 
ing factor. There is no one best brass furnace, but for any specific 
purpose and locality there are types that are more efficient and those 
that are less so. Elimination of unfit types for the purpose in hand 
may better be effected by considering, first, the quality and quantity 
of molten metal they should produce, and, second, their fuel effici¬ 
ency, first cost, and upkeep charges. 

ESTABLISHMENT OF STANDARDS OF FURNACE OPERATION. 

After the furnaces have been selected, standard conditions for 
their operation should be designated and maintained. Such a 
standard involves seeing that the fuel supply is of the proper grade, 


° Knoeppcl, C. E., Maximum production in shop and foundry, 1911. 





ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 


251 


that blowers, oil pumps, and. all other appurtenances of the furnace 
selected are kept in proper condition. The metallurgist should make 
tests of his furnaces to determine the melting speed of which they 
are capable, the maximum fuel efficiency, and the minimum melting 
loss that they can give, with proper operation, on the alloy used, and 
should designate the results as the standards. He should then train 
his furnace tenders so that the daily operation of the furnaces meets 
the standards. 

To get the highest efficiency from any type of furnace, it should 
be run at its maximum speed; that is, the metal must be poured and 
a new charge put in the furnace just as soon as the metal reaches 
the proper pouring temperature. This practice gives the greatest 
production, the highest fuel efficiency, the lowest metal loss, and the 
least gas absorption. Fewer furnaces run at full speed will be more 
economical than a larger number run at less than their limit of speed. 
“Soaking” the metal is bad from every point of view. Holding the 
metal in the furnace while waiting for the molds involves “soaking.” 
The less “fool proof” the furnace, the worse the result of holding 
the metal. A case in point is cited by Dean.® In a coal-fired, rever¬ 
beratory furnace, melting manganese bronze, when the melt is wait¬ 
ing for the mold, an addition of 2 or 3 pounds of zinc per hundred¬ 
weight of the metal is necessary to keep the alloy at the desired 
composition. 

In order to have the molds ready when the metal is ready, the 
supply of molten metal and the production of the molds must be 
properly balanced. This relation involves producing both at a 
known rate, and necessitates previous planning so as to have both 
ready simultaneously. The foundry man can easily see that his 
management is not scientific when the molders are idle because all 
the flasks for a given job are ready to be poured and the metal is not 
ready. He is not so likely to realize that losses of fuel, of metal, and 
of quality of metal are also going on when the metal is waiting for the 
mold. Perfection can not always be readied, and it may be less 
costly to “soak” the metal than to have the molder idle, but if such 
a case now and then occurs, the manager should realize that ho is 
putting his furnaces at a disadvantage, and that the high fuel con¬ 
sumption, the high metal losses, and the bad castings from the gas in 
the metal are due, not to anything inherent in the furnaces, but to 
his failure to operate them on a proper schedule. 

That there is, in ordinary practice, or even in practice better than 
the ordinary, a considerable discrepancy between fuel consumption 
and metal losses on a test and in regular practice is easy to demon¬ 
strate. In this connection, figures are given by Hansen 6 on two 

a Doan. W. It., Foundry tests and foundry practice: Trans. Am. Inst. Metals, 1912; Metal Ind., vol. 10, 
1912, p. 449. 

b Hansen, C. A., Electric melt ing of copper and brass: Trans. Am. Inst. Metals, 1912, advance copy, p.0. 




252 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


makes of open-flame oil furnaces, melting an alloy containing about 
1(5 per cent of zinc. Furnace A, under test, used 2.02 gallons of oil 
per hundredweight of metal melted, the metal lost being 2.2S per 
cent. Under operating conditions, furnace A used 3.4(5 gallons of oil 
per hundredweight, 5.82 per cent of metal being lost. 1* urnace 15, 
under test, used 1.78 gallons of oil per hundredweight, 1.81 per cent 
of metal being lost, whereas, under operating conditions, it used 1.97 


gallons of oil per hundredweight, the metal lost being 2.50 per cent 

Another illustration is furnished by the special test described under 
Reply 16. In that test the gross melting loss in melting red brass 
in four forms of oil furnaces and in a coke furnace ran between 0.63 
and 0.8S per cent, whereas the gross loss in ordinary practice is given 
as 3 per cent. 0 

The low loss on gun metal in the special test described in Reply 79, 
covering three different types of furnaces that gave gross losses of 
0.42 to 0.54 per cent, might be compared with ordinary practice. 
Reply 19 describes tests in which the losses were 2.25 and 2.43 per 
cent, whereas the figures for regular practice are 5.4 per cent gross 
and 4.4 per cent net. 

The recovery of metal from ashes and spillings represents metal that, 
with the same care in regular operation that is taken in tests, would 
have gone where it was desired and would not have had to be recov¬ 
ered, to say nothing of what was lost and not recovered. 

There is, of course, a point at which care costs more than the fuel 
or metal lost, but the foundry or mill that has reached this point is 
remarkable. The figures for fuel consumption and metal losses 
shown in painstaking tests, and, in many cases, by the catalogues of 
furnace makers, can not always be economically reached in the 
hustle of every-day production, yet they form a standard, and the 
manager should know how far away from that standard his daily 
work is, and whether it is cheaper to allow the discrepancy or to 
correct it. 


FOUNDRY RECORDS OF FURNACE OPERATIONS. 

In order to maintain the standards of speed, fuel consumption, 
and metal losses that have been established, a prompt and accurate 
record of the performance of the furnaces is essential. Some few 
plants, notably some rolling mills, keep a daily record of the per¬ 
formance of the furnaces run by each caster. The record covers the 
production, the metal lost, the recovery from the ash, the fuel con¬ 
sumption, and the amount of metal produced that is defective through 
improper melting. The records may form the basis for an efficiency 
reward or system of bonus pay for work done according to instruc¬ 
tions. They at least allow the manager to know at all times whether 


a See subdivision 1 of tho large table. 




ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 253 

tlie production of his furnaces is reaching the standard, and if not, 
to find out the cause and remedy it at once. Contrast this facility 
with the conditions in so many plants where coal or coke is never 
weighed for the furnace charges, oil furnaces are not metered, and no 
idea at all can bo formed of the melting losses. The mechanical 
equipment of many plants is admirable and the quality of work high, 
and yet the operation of the furnaces may be utterly extravagant in 
fuel and metal losses. If the same care and thought were put on the 
elimination of these losses that has been given by the management 
to other parts of the plant, the losses would be vastly reduced. 

The calculation of fuel consumption and metal losses figured from 
a yearly or even monthly inventory is of little or no aid in furnace 
control. In order to detect waste in furnace operation, the figures 
must be available at the exact time that the wasteful condition 
occurs, and must promptly reflect increased or decreased efficiency, 
a result that involves the daily or, at the least, the weekly summation 
of the furnace records. Several of the plants visited or replying to 
the questions had proper records, and more were just starting to 
attain them, but the total number of plants that keep records of 
any adequacy is exceedingly small. Of the 1,650 plants receiving 
the list of questions, only 230 replied with any data, and about 50 
stated that no records at all were kept. It is a fair inference that few 
of the 1,420 that did not supply data keep adequate records. Of 
the 230 that did reply, about 30 keep records sufficient to keep the 
management continually informed of the efficiency of the furnaces and 
the metal loss, some 40 have records that would be more or less useful, 
and 10 have made furnace tests but have no regular records. The 
other 150 either state explicitly that they keep no records on the 
details mentioned above, or that the figures reported are only esti¬ 
mates, or else, in about 30 cases, the figures are seemingly derived 
from an inventory, taken in such a way as to give no real accuracy. 
To the inaccuracy of the estimates are due a great many of the 
inconsistencies in the different replies to the list of questions. 

It is doubtful whether there are 50 firms in the country that know 
how their furnaces are running with sufficient exactness from day to 
day to allow the correction of avoidable wastes. The firms that 
have such knowledge almost invariably have a metallurgist who has 
supervision of the melting room, and almost always have the lowest 
losses. 

Although more and more firms, particularly the largest ones, are 
dropping into the line of progress, the great majority still run their 
melting rooms without records, and in the way so vividly described 
by Redfield,® in a chapter on “The Days of the Rule of Thumb.” 


a Redfield, W. C., The new industrial day, 1912, pp. 18-40. 



254 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


SUGGESTIONS FOR FURNACE TESTS AND RECORDS. 

No general rules for making tests of furnaces or for keeping furnace 
records, nor, still less, any set forms, can be laid down that will he 
applicable to the varied conditions in all plants melting brass. A 
few details that should be kept in mind in planning either furnace 
tests or a system of daily records, and some of the variables in regard 
to the nature of tho castings made that must be considered in com¬ 
paring results from various foundries may, however, be briefly 
outlined. 0 The data should cover tho variables involved in determin¬ 
ing tho suitability of tho furnace for tho particular conditions of the 
user, fuel cost, attendance cost, crucible cost, speed of melting, 
oxidation and volatilization losses, and quality of metal produced, 
and should contain answers to the following questions: 

Questions that should be answerable from records of furnace tests or operations. 

NATURE OF WORK AND SPECIAL CONDITIONS. 

1. Ih the plant a rolling mill casting ingot only; a part of a manufacturing plant, 
making large numbers of similar castings; or a jobbing foundry with a varied run of 
work? 

2. Naturo of castings (as plumbing goods, auto parts, etc.); bench or floor work; 
heavy or light; average weight per casting; ratio of weight of gates and sprues to 
castings. 

3. Is work so light as to require very hot metal? Average temjierature in furnace? 
Average pouring temperatures? 

4. After the metal is hot enough to be poured, is it usually held in the furnace to 
await the preparation of molds? Could you get more heats per day from one furnace 
if you could use the metal, or are all furnaces running used to fullest capacity? 

5. Which of the factors mentioned below chiefly influenced you in your choice of a 
furnace for your work: 

(а) First cost of furnace and equipment. 

(б) Cost of upkeep. 

(c) Cost of attendance. 

(d) Cost of crucibles. 

(e) Cost of fuel. 

(/) Oxidation and volatilization losses. 

(g) Quality of metal produced. 

( h ) Speed of melting. 

(i) Convenience and sanitary conditions. 

FURNACE CONSTRUCTION. 

6. Type of furnace. —Coal or coke, gas, oil, or electric; pit or tilting; crucible sta¬ 
tionary or removed to pour; natural or forced draft (in ounces or pounds per square 
inch); stack dimensions; number of furnaces; size of combustion chamber; height 
of crucible blocks; power used in blower; compressor or oil pump serving furnaces; 
pressure of oil or gas and of air at burner; oxidizing or reducing flame. 

7. Fuel. —If coal and coke, analysis and British thermal units per pound; if gas, 
British thermal units per cubic foot; if oil, specific gravity (state at what temperature) 
and British thermal units per pound. 

8. Size and shape of crucible or melting chamber; material; capacity per charge 
(state in pounds of metal). 

°8e« OiUett, II. W., Letter from committee on cooperation with the Bureau of Mines: Am. Inst. 
Metals Bull. 19, Dec., 1912, p. 17. 




ADVANCES POSSIBLE WITH PRESENT EQUIPMENT. 255 

SPECIFIC INFORMATION FOR EACH TYPE OF FURNACE. 

9. Duration of test reported. 

10. Total pounds of metal melted in period; pounds of new metal (state whether 
ingot, wire, or punchings); pounds of alloyed metal (state whether gates, sprues, or 
large scrap); pounds of alloyed turnings. 

11. Gross loss, including metal recovered; net loss; net percentage of oxidation and 
volatilization loss, corrected. Does this include grinding losses? 

12. Quantity of fuel used per hundredweight of metal melted. 

13. Crucible life in number of heats per crucible and in crucible cost per hundred¬ 
weight of metal melted. 

14. Character and extent of furnace repairs, linings, etc., during period. 

15. Number of furnaces per furnace tender. 

16. Number of pounds of metal melted per furnace tender per hour. 

17. Average time required to melt 1 hundredweight of metal per furnace. 

18. Composition and tonnage of the different alloys melted in the period. 

19. Discussion of quality of metal melted in different batteries under test. 

To get the information outlined above, separate records are neces¬ 
sary for each battery of different types of furnaces in foundries using 
more than one type. Furnace results should not be lumped from 
two or more of the following types: Coke, pit; coke, tilting; oil or 
gas, with flame impinging on metal; oil or gas with crucible stationary; 
oil or gas with crucible pulled to pour. For obtaining records as to 
fuel consumption, coal or coke may be weighed into bins and used 
only for melting during the period of a test; oil or gas should be me¬ 
tered and none taken in front of the meter for other purposes. Fuel 
used to preheat pouring crucibles or ladles should go in with that used 
for actual melting, as it is a charge against the type of furnace that 
requires pouring crucibles or ladles. Power used in producing air 
blast or oil pressure for furnaces should be charged against the 
melting cost. 

Records of crucible life and furnace repairs are most easily kept 
by the head furnace tender. Pouring crucibles or ladles used up 
in the test period are a charge against tilting furnaces. Attendance 
costs are best kept by the accounting department, which should 
know daily the number of furnaces going in each battery, the num¬ 
ber of furnace tenders employed, the hours worked by each, and 
the number of heats per day, as well as the quantity of metal melted. 
The four great items are fuel cost, labor cost, crucible cost, and 
“shrinkage,” or metal lost by oxidation and volatilization. Records 
of the first three are more easily kept than of the last. The actual 
melting loss in furnaces only is hard to get under foundry conditions. 
If a crucible of metal is poured into many small molds, the oxidation 
and volatilization during pouring is greater than if poured into a 
single large mold. Loss on remelting grindings is greater on small 
castings with many gates and sprues. These losses are chargeable 
to the patterns used and not to the furnaces. One way to get melting 
losses only is to weigh pouring crucibles or ladles plus molten metal 


250 BRASS-FURNACE PRACTICE IN THE UNITED 8TATE8. 


and to allow taro for tho empty ladles or crucibles; or the castings 
may be weighed at the grinding room, the weight of the attached 
gates and sprues being included, but tho core and molding sand being 
knocked off; proper credit should be given for both good and defective 
castings and for any skulls or metal poured into ingot instead of 
into castings. In this case the furnaces should not be credited with 
grindings recovered, or with anything else recovered except theskim- 
mings, spillings, etc., obtained in the melting room and in the molding 
room. 

A less satisfactory but more common way is to include the grinding 
losses and to credit the furnaces with the weight of the good castings, 
the defective castings, the gates and sprues, and all metal recovered 
from skimmings, spillings, and grindings, the weighing being done 
after the castings have passed the grinding room. 

In any case it is essential that the furnaces be debited with all 
new metals, composition ingot, gates, sprues, or large scrap, and bor¬ 
ings or grindings received daily from the metal stock room, being cred¬ 
ited with any such metal returned unmelted, and with the total 
castings, gates and sprues produced, as well as with the metal recov¬ 
ered by the recovery department (less the cost of recovery, which 
can be figured into equivalent pounds of metal). The value of any 
tailings, etc., sold can be converted into equivalant pounds of metal 
and credited to the furnaces.® 

In order to obtain figures on true melting loss, it is imperative that 
the remelt of gates, sprues, and defective castings be not neglected. 
Such a record involves having a metal stock room to which all gates, 
etc., go, and from which they are charged out to the furnaces, rather 
than having the gates brought back to the furnace and remelted 
without any record. Usually the best method is to make up the fur¬ 
nace charges in the metal stock room, each separate charge being 
sent to the furnace in a tray or tote box. In some plants the weighing 
is semiautomatic, and the charges are mechanically conveyed to 
the furnaces. 6 

When prompt and accurate records are obtained, tho next thing 
for the management to do is to utilize them. A prescription is of no 
valuo unless it is taken, and unless the manager takes steps to remedy 
wrong conditions when his furnace records or graphic charts show 
that they exist, he might as well not have them. 

a See Olsen, L. W., A system of distributing waste losses in raw material to the cost of finished products: 
Trans. Am. Brass Founders’ Assn., vol. 3,1909, p. 9. 

ft Thompson, G., A model metal-casting shop of the Naugatuck Valley: Metal Ind., vol. 11,1913, p. 207. 



BRASS-FURNACE PRACTICE IN THE UNITED STATES. 257 


CAUSES OF DISEASE AND DANGER AND ESSENTIALS 

FOR HEALTH AND SAFETY. 

One of the most important essentials is that proper attention be 
given to conserving the health and promoting the safety of employees. 
In this connection Dresser® says: 

On the whole, the movement in behalf of efficiency means an intelligent effort to 
provide for individual work under conditions more favorable for all concerned. It 
therefore becomes a matter of scientific necessity to provide for the welfare of each 
employee. W hen it is a question of the best work each can do, work that is performed 
in the best manner, attention must be given to any number of conditions that would 
otherwise be neglected. Accordingly more heed is paid to sanitary conditions, to 
the number of hours, and the conditions under which each employee can work to 
greatest advantage. 

The problems of furnace design, construction, and operation in 
their effect on the waste of metal and fuel are receiving attention in 
up-to-date foundries and mills. Those of the effect of the construc¬ 
tion and operation of plant and equipment on the waste of the 
workmen’s health and of their lives are also being earnestly studied by 
the brass industry. Plants whose motto is “Safety first and profits 
second” are no longer rarities. Much, however, remains to be done. 

Brass founding is commonly regarded as an unhealthful occupa¬ 
tion, although the operations that comprise the bulk of the work in 
molding and core making do not in themselves involve anything that 
can bo classed as unhealthful. The unhealthful part of the brass- 
foundry business comes from excessive heat, smoke, dust, or fumes 
incident to melting the metal, to pouring it into the molds, knocking 
the cores from the castings, sawing off gates, grinding castings, sand 
blasting, etc. Each of these operations can readily bo so safeguarded 
as to be without injurious effect on the health of the workers. 

The bad reputation of the brass foundry in regard to health is due 
more to the construction of the older foundry buildings than to any¬ 
thing inherent in the trade. 

Most industries that deal chiefly with hand labor show a slower 
improvement in housing and in general working conditions than 
those requiring high-grade machinery. Also, industries that roquire 
little equipment and few workers are slower in showing improvo- 
ment on lines of health and safety than those that naturally tend 
to centralization and the employment of large numbers of workers. 
Brass foundries, even to-day, have little machinery in comparison 
with that used hi most industries, and the machinery is of heavy 
type. Up to recent years foundries have been of rather small size, 
with few workers. Tho foundries doing purely jobbing work as a 
class aro distinctly behind tho foundries run as an adjunct to largo 

a Dresser, H. W., Human efficiency, 1912, p. 3. 

44712°—Bull. 73—1G-17 




258 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 

manufacturing plants. In such plants tho construction of modern 
shops and a largo total number of workers have brought their foundry 
departments to an advanced point in surroundings and sanitation 
that tho jobbing shops as a class have yet to reach. 

The words “brass foundry” usod to bring up a mental picture of 
a low wooden shack, poorly arranged, with perhaps a number of 
sheds or small rooms that wore added to tho original building as tho 
business expanded (a condition so common that such additions has 
gained the name of “dog house”). Tho buildings wore poorly 
lighted, poorly ventilated, often not heated at all excopt by tho 
melting furnaces, cold in winter, hot in summer, always full of smoko 
and fume, grimy with tho accumulated dust of scores of years, and 
with toilet and lavatory facilities of the crudest sort. 

This picture is rapidly giving way to one of a high, light, airy 
structure to which a superintendent need not bo ashamed to take a 
visitor after showing him through a modern machine shop. Dirt 
there is, and must be, nor will tho stage bo reached where white- 
flannel trousers and white collars are suitable attire for the foundry- 
man at his work, but there is little excuse for dirt of a nature that 
will be harmful to health. 

“BRASS SHAKES.” 

The main reason why the brass industry is classed as unhealthful 
is found in tho occupational disease known as “brass-founder’s 
ague,” or, more commonly, “brass shakes,” or “spelter chills.” 

Tho symptoms® of “brass shakes” are a dry throat, a general 
feeling of lassitude, a hacking cough, a dull headache, a feeling of 
oppression in tho chest, difficulty of thoracic broathing, and sometimes 
a feeling of nausea. In a few hours, but usually not until the subjoct 
leaves tho furnaces in the evening, so that perspiration ceases, 
a slightly chilly feeling occurs, which increases to a distinct rigor, 
tho subject shaking violently. During the chill, tho actual tempera¬ 
ture may rise to as high as 103° F. The chill is accompanied by 
muscular pains. After a few hours tho chills cease rather suddenly 
and a profuse perspiration sets in. The attack is then over and tho 
patient sleeps profoundly, rising in tho morning with only a slight 
feeling of weakness. Zinc is eliminated in the urine and feces, and 
its presence is suspected in the perspiration also. Swelling of the 
spleen and albumen in the urine are also sometimes reported. 

The disease is somewhat similar to malarial ague. There is no 
specific remedy. The chilly feeling creates a desire for warming 
drinks, and the workmen commonly drink alcoholic stimulants to 
satisfy this desire. Alcohol, however, is not only not a remedy but 


o Compare Sperry, E. 8., Spelter chills: Brass World, vol. 7,1911, p. 40. 




ESSENTIALS FOR HEALTH AND SAFETY. 


259 


makes the worker far more susceptible to the attacks. This result 
is indicated by a dozen replies to the list of questions issued in 
this investigation, and is so well recognized that the disease is often 
termed “whisky shakes” or “booze shakes.” Although abstainers 
and moderate drinkers may have the “shakes,” the ailment is far 
more common among heavy drinkers. Hot milk, milk and eggs, 
and milk and pepper, taken in large quantities, and the use of a mild 
purgative shorten the attack and decrease its severity, the zinc prob¬ 
ably being precipitated as an insoluble albuminate. This treatment 
may also ward off an attack. 

The theories as to the exact agent that causes the disease are varied, 
the blame being variously laid on zinc oxide, metallic zinc, arsenic, 
cadmium, copper, a mixture of copper and zinc, or carbon monoxide, 
and Hayhurst a suggests zinc carbonyl. 

Of these the most probable cause is zinc oxide, 6 the main con¬ 
stituent of the fumes. It is unlikely that metallic zinc reaches tho 
lungs unoxidized. No definite proof has been adduced to show that 
the minute traces of arsenic that may be present as an impurity are 
the cause. Cadmium is far more volatile than zinc, practically all 
the cadmium in the spelter being lost. c 

Copper fumes may cause poisoning , d but no copper is volatilized 
by the ordinary temperatures of brass melting, though traces may be 
mechanically carried by the zinc oxide. Hansen does not mention 
chills in his account of copper poisoning. However, the symptoms of 
poisoning by copper fume and those of poisoning from mercury 
vapor both have some resemblance to those of “brass shakes,” 
Kisskalt e finding that the symptoms of poisoning by the inhalation 
of various metal vapors were more similar than when the metals 
were absorbed through other causes. 

Carbon monoxide headaches are reported in some plants where 
oil furnaces are installed without any attempt at hooding, but the 
symptoms aro quite distinct. Moreover, Siegel/ has shown the 
absence of carbon monoxide hemoglobin in the blood of patients 
suffering from the “shakes.” 

Zinc carbonyl deserves no serious consideration for, as Mond o 
%/ 

states, the carbon vis of nickel and iron are the only ones that can be 

/ V 

a Hayhurst, E. II., Occupational brass poisoning—brass-founders’ ague: Am. Jour. Med. Sci., vol. 
145,1913,p. 752. 

6 Iiambousek, J., Gewerbliche Vergift ungen, 1911, p. 190. 

c Bassett, W. H., Zinc losses: Jour. Ind. Eng. Chem., vol. 4,1912, p. 164. 

d Hansen, C. A., Copper poisoning: Met. Chem. Eng., vol. 9,1911, p. 67; Jour. Inst. Metals, vol. 5,1911, p. 
304. 

t Kisskalt, fiber das Glessfieber und verwandtegewerbliche Metalldampfinhalationkrankheiten; Zeitschr. 
Hyg. und Infectionkrank, vol. 71,1912, p. 472. 

/ Siegel, J., Das Giessfieber: Vrtjsche. geruchtl. Med., vol. 32,1906, p. 174. 

g Mond, L., Note on the volatilization of heavy metals by means of carbon monoxide: Trans. 7th Int. 
Cong. App. Chem., sec. 2, 1910, p. 8. 


260 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


formed at atmospheric pressure, cobalt carbonyl requiring 100 
atmospheres and molybdenum and ruthenium carbonyls 450 atmos¬ 
pheres; no others are known. 

The fumes from the purest zinc are known to give rise to attacks 
of “spelter chills” exactly the same as “brass shakes’ * are known in 
zinc smelters. It has been thought that zinc was not the cause be¬ 
cause hot galvanizers and workers in almost pure zinc castings do not 
have the “shakes.” Reference to figure 2 will indicate that the reason 
for this is simply that the working temperatures represented aro below 
the point at which pure zinc is appreciably volatile. 

. Some persons, especially those not indulging in alcohol liquors, are 
naturally immune from the “shakes.” Most others, if constantly 
breathing small amounts of zinc fumes, develop practical immunity, 
and have the “shakes” only when they get an overdose of fume, as 
when ventilation is poor, or after a day of rest, when the system 
becomes freer from zinc. Monday night is the time when most cases 
of “shakes” occur, both because the system rids itself of some zinc 
over Sunday, and in some cases, because the Saturday night and 
Sunday indulgence in alcohol puts the system in such condition that 
the subject is more susceptible. Most rolling mills have trouble 
from “shakes” when cold weather sets in and ventilation is reduced. 

A few workers do not develop much of any immunity and have to 
abandon working amid zinc fumes, but such cases aro rare. As a 
certain natural immunity exists, one method of cutting down the 
number of foundry workers attacked by “shakes” suggests itself. 
Instead of having each molder pour his own molds, the pouring may 
be done by a pouring gang whose task is pouring only, an arrange¬ 
ment that also has advantages as regards production. If the pouring 
gang is composed of immunes, and the molders keep out of the fume 
while their molds are being poured, fewer cases of “shakes” would 
be expected. 

The “shakes” are inconvenient and unpleasant, but seldom or 
never fatal, very few cases ever coming under the hands of a doctor. 
The ailment may, however, cut down the efficiency of the worker, 
and its occurrence in a shop is an indication of conditions that can 
not promote the physical good of any of the employees, even those 
not appreciably affected. 

Whether it actually does permanent physical harm is a subject for 
controversy.® Everyone grants that it involves temporary discom¬ 
fort, and some writers claim that it lowers the bodily resistance, so 
that other ailments, particularly pulmonary diseases, are more readily 
contracted, and that the average life of brass melters and casters 
is thereby reduced. 


a Jones, J. L., Zinc poisoning : Metal Ind., vol. 11,1913, p. 42. 




ESSENTIALS FOR HEALTH AND SAFETY. 


261 


Kambousek a states that casters who have had repeated attacks 
of the “shakes” may become emaciated and may contract digestive 
disorders and catarrah of the respiratory organs as a result of chronic 
zinc poisoning. 

lie further states that attacks are likely to bring palpitation of 
the heart or asthma. If asthma be considered synonymous with 
mere shortness of breath, the statement is doubtless true. However, 
the author, though subject to attacks of true asthma since childhood, 
and though extremely sensitive to some of the exciting causes of hay 
fever, particularly the odor of a sweaty horse, has never developed 
an attack of asthma from exposure to zinc fumes, notwithstanding 
the fact that on a number of occasions such exposuro has brought on 
all the ordinary preliminary symptoms of “brass shakes” save that 
of nausea, the “shake” ending in distinct chills, though seldom of 
such severity as to cause actual shaking. 

Hoffman b gives the normal male mortality from consumption as 
14.8 per cent, and states that the mortality from consumption among 
brass workers is 3S.9 per cent. His figures for brass workers include 
workers who grind castings as well as those who melt and cast metal. 
As he gives the percentage of mortality from consumption for grinders 
alone c as 49.2, the figure for deaths from consumption among brass 
melters and casters would be less than 38.9 per cent. Statistics 
cited by Hoffman for England and Wales during 1900 to 1902 show* 
a slightly higher mortality among brass workers than the normal 
figure for occupied males, but the figures are not in sufficient detail 
as to the various branches of brass working to throw much light on 
the effect of u brass shakes.” 

Oliver d states that out of 1,200 casters in Birmingham only 10 
were more than 60 years of age. 

Krom e admits that pneumonia and consumption are common. 

Hayhurst^ finds only young men in the brass foundries of Chicago, 
and claims that iron founders as a class are older than brass founders. 

Hayhurst 0 also makes the following statement: 

A single attack of brass chills is in itself not dangerous, and as they come on usually 
at night time the workmen rarely lose any time from work, at most not more than the 
day following the chill. Once back and at work they become rapidly inured and no 
longer subject to the chills. But the constant repetition of these chills, or the con¬ 
stant exposure to the conditions producing them, ultimately ends in chronic diseases, 
usually affecting the lungs, digestive tract, nervous system, and kidneys. 

a Rambousek, J., Gewcrblieho Vcrgiftungen, 1911, p. 233. 

b Hoffman, F. L., Mortality from consumption in dusty trades: Bull. U. S. Bureau of Labor, No. 79, 
1908, p. 667. 

c Hoffman, F. L., op. cit., p. 649. 
d Oliver, T., Dangerous trades, 1902, p. 461. 

e Krora, L. J., Dangers of the easting shop: Metal Ind., vol. 8,1910, p. 172. 

/ Hayhurst, E. H., Occupational brass poisoning—brass-founder’s ague: Amer. Jour. Med. Sci., vol. 114, 
1913, p. 728. 

0 Hayhurst, E. H., Report of Illinois Commission on Occupational Diseases, 1911, p. 56. 



262 


BRASS-FURNACE PRACTICE IN THE UNITED STATER. 


Following the publication of the report of the Illinois Commission 
on Occupational Diseases, there were a number of articles in the popu¬ 
lar magazines in which lead poisoning, phosphorus poisoning, and 
“brass shakes” were treated together, and the general impression 
was given to the public that all three occupational diseases were in 
the same class. This classification has been resented by many of 
the representative men of the brass rolling mills of Connecticut, who 
expressed themselves strongly on the subject when their plants were 
visited. One superintendent stated that “brass chills’ had no more 
permanent harmful effect on the human organism than seasickness, 
and that as his casters averaged only one slight attack of “shakes” 
per year—at the beginning of cold weather—he objected to having 
the public misled into considering that the conditions in his mill were 
on a par, in regard to dangerous occupational diseases, with those 
in the white-lead industry and the match industry of former days. 

Some of these men were inclined to discredit the investigations 
of medical men who had made errors in their statements in regard 
to brass furnaces and alloys, such as, for instance, the statement that 
the cupola furnace was the preferable type, or that copper boils at 
1 , 300 ° C., both of which are highly incorrect. Thus the rolling- 
mill men may not have given due weight to the medical facts on which 
these writers can speak with authority. 

It must be admitted, however, that in the Naugatuck Valley of 
Connecticut where more alloys high in zinc are melted than in all 
the rest of the country combined, and where the true facts as to the 
danger or harmlessness of “brass shakes’’ should be best known, 
neither the management nor the casters themselves consider “brass 
shakes” permanently harmful. Bassett ° says: 

The effect of the zinc fumes on the health of the casters, in the ordinary casting 
shops, at least those connected with the wrought-brass industry, are not any more 
harmful to health than is the use of tobacco. Throughout the large mills of Connec¬ 
ticut you will find as fine-looking men engaged in casting brass as you can find in any 
trade where the work is carried on in intense heat. They are mostly big, husky men 
who enjoy life to a good old age, and do not seem to mind the effect of the zinc. Occa¬ 
sionally there are men who do not seem able to stand the work, the same as in any 
trade where work is severe and hot, but in almost every instance the casters of brass 
are healthy and apparently not injured in any way by the zinc fumes which, to people 
who are not accustomed to them, are quite troublesome. 

The casters merely laugh when “brass shakes” are mentioned and 
do not seem to fear them in the least, as it is extremely rare for an at¬ 
tack to be so severe as to involve absence from work and loss of pay. 

The attitude of the managers may be biased, and that of the casters 
may be due to too great familiarity with the disease to give it its true 
significance. The writer talked with a number of chemists and 
metallurgists of the Connecticut and other rolling mills. These men 

o Bassett, W. H. (In discussion): Jour. Ind. Eng. Chem., vol. 4,1912, p. 167. 





ESSENTIALS FOR HEALTH AND SAFETY. 


263 


have almost all had considerable experience with “brass shakes,” 
as their work takes them intermittently to the casting shop where 
they inhale enough zinc fumes to give them the “shakes,” but seldom 
enough to develop the immunity enjoyed by the casters. They are 
far enough from either the managerial or the workman’s point of view, 
it would seem, to form an impartial opinion. Their opinion is that, 
although the “shakes” are unpleasant, they produce no lasting 
harmful effects, and that a man’s efficiency after an attack is not 
much more reduced than would be the case after the loss of the same 
amount of sleep as is usually involved in an attack. 

Dr. G. B. Cowell, of Bridgeport, Conn., one of the rolling-mill 
centers adjacent to the Naugatuck Valley, became interested in the 
subject of “brass shakes,” as his father and two brothers were casters, 
and he himself had worked at the trade in his college vacat ions. No 
cases had come to him for professional treatment, as the men afflicted 
almost never seek medical aid. However, he sent out a list of ques¬ 
tions to 20 representative brass mills of his district, asking informa¬ 
tion on the number of casters and caster’s helpers empk^ed, their 
age, the length of time they had worked at the trade, data on the 
illness or death of casters, influence of the use of alcohol, preventive 
measures, etc. 

As the professional standing of Dr. Cowell and the accuracy 
of the data collected by him have been vouched for by half a dozen 
men of high standing in the rolling mills of that district, his data 
should be of interest. He obtained figures on 206 casters and 145 
helpers, finding 1 caster who was SO years old and had been a 
caster for 50 years, though not then actually in the mill, as lie had 
been incapacitated by a faff. Two others had worked at the trade 
for 40 years, 14 for 30 years, and 66 for 20 years. Five casters 
were 60 years of age, and 20 over 55. The ages were in full: 

Period of service of workers in the rolling mills of one district. 


Years. 

Number 

of 

casters. 

Number 

of 

helpers. 

20 to 30... 

18 

51 

30 to 40... 

76 

56 

40 to 50... 

72 

32 

50 to 60... 

35 

4 

60 to 70... 

5 

2 


The death rate from consumption among casters is given by him 
as 2.5 per 1,000, and the general figure for Connecticut as 4 per 1,000. 
He finds the average air space per worker in the 20 casting shops 
to be 9,697 cubic feet per man, ranging, in 19 cases, from 18,000 to 
4,200 cubic feet per man. The air space required in English casting 
shops is 3,500 cubic feet per man. One plant fell to 2,375 and its 








264 


BRA86-FUBNACR PRACTICE IN THE UNITED STATES. 


workmen had trouble from the “shakes.” Habitual users of alcohol, 
he finds, are liable to more frequent and more severe attacks of 
chills than are abstainers or moderate users. Connecticut casters 
as a class, however, bear about the same relation to the average 
brass-mill worker as the members of the football team do to the 
average student body of a university, so that comparative figures 
for death rates or ages are not conclusive as to the effect of “ brass 
shakes” on the average men. Yet it seems probable that the high 
temperatures in which the casters work and the effect of going out 
doors in winter while perspiring freely, as casters commonly do, 
may have as much to do with the commonly alleged liability of 
brass melters to consumption as do the attacks of “brass shakes.” 

That the harmful effects of “brass shakes” are not to be classed 
with those of other industrial poisonings, such as by lead and phos¬ 
phorus, is indicated by that fact that such good authorities as Wins¬ 
low® and Tolman and Kendall b do not specifically mention “brass 
shakes.” Winslow merely states that among a list of other metals 
zinc is responsible for more or less trade disease. 

Whatever view be taken of the ultimate effect of repeated attacks 
of “brass chills,” they are unpleasant, probably decrease theefli- 
ciency of the worker immediately after an attack, and may possibly 
decrease the bodily resistance to other diseases. 

Hence, although it is manifestly unfair to the brass industry to 
class “brass shakes” with lead or phosphorus poisoning, yet every 
precaution should be taken to prevent them. 

PREVENTION OF “BRASS SHAKES.” 

To prevent the “shakes” the zinc fume must not be allowed to 
enter the nose or mouth. The use of respirators is possible, but 
they are seldom employed, as the men prefer an occasional attack 
rather than the continual discomfort of wearing the respirator. A 
few plants report that respirators are provided free for those who 
wish them, and in two plants their use is compulsory whenever 
yellow brass is poured. As enough fume to develop immunity is 
not present in foundries where yellow brass or manganese bronze 
is seldom poured, and as the small amount produced would not 
warrant installing forced ventilation, the inconvenience from “brass 
shakes” may be as great and the cases as many as in rolling mids 
where alloys high in zinc are constantly poured, but where there is 
proper ventilation and where immunity is developed. Hence in 
the plants where alloys high in zinc are poured only occasionally, 
the wearing of respirators during such pouring should be made 

a Winslow, C. E. A., The prevention of industrial poisonings: Proc. 8th Int. Cong. App. Chem., 1912, 
vol. 2n, p. 309. 

t> Tolman, W. 11., and Kendall, L. B., Safety, 1913. 



ESSENTIALS FOR HEALTH AND SAFETY. 


265 


compulsory. As the toxicity of the zinc fume probably exists 
whether the fume be inhaled or swallowed, eating food or chewing 
tobacco in the presence of zinc fume or without previous washing 
of the hands and face should be prohibited. 

Some of the fume may be caught by the use of a cover placed 
over the pouring ladle or crucible and having a small opening to 
allow pouring of the metal. One form of such a cover is described 



Figure 22.—Covers for pouring crucibles or ladles to hold back zinc fumes. 


by Primrose, 0 another is on exhibition at the American Museum 
of Safety, New York City, and still others are on the market; two 
forms are illustrated in figu es 22 and 23. 



A firm that has tried one such cover, which was designed to skim 
the metal during the pouring as well as to hold back fumes, reports 
that the cover did not properly skim the metal and that its use 
involved considerable trouble; hence it was discarded. As this firm 
does not cast yellow brass, it did not con¬ 
sider itself in a position to decide whether 
the holding back of the zinc fume would 
outweigh the trouble involved in using 
the cover. 

No trouble from “shakes” is reported 
from any plants dealing only with bronze, 
red brass, or other alloys low in zinc, save for one isolated case where 
cupronickel, free from zinc, was melted in a battery of furnaces 
sometimes used for yellow brass, but no alloys containing zinc W'ero 
beingmelted at the time the attack w r as contracted. The symptoms 
were thought to bo the same as in the ordinary “shakes.” This is 
the only case of its kind reported, and in general no trouble need be 
feared from red brass and little from “half yellow and half red” 
brass if ventilation is good and the pouring temperature low. 


Figure 23.—Another type of cover 
for holding back zinc fumes. 


a Primrose, II. S.. Discussion of modern brass founding: Foundry, vol. 40, 1912, p. 300; Castings, vol. 
10,1912, p. 174. 








260 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


In dealing with “half yellow and half rod” alloys poured very hot, 
with yellow brass, manganese bronze, or German silver, the men 
should be warned against inhaling zinc fume, and advised to use 
respirators (which should be provided free by the management) and 
to drink milk to alleviate the “shakes,” and should bo told that the 
use of alcohol makes them more likely to have the “shakos.” Notices 
containing such information should be posted or given to the men. 

One notice used for this purpose is as follows: 


CAUTION. 

The fumes given off during the melting and pouring 
of brass, lead, tin, antimony, zinc, or bismuth are 
poisonous, and should be avoided as much as possible. 

Excessive inhalation of the fumes of these materials 
may bo the cause of mild forms of metallic poisoning, 
indicated by temporary illness, such as the feeling of 
exhaustion, nausea, marked pallor, and chills. 

REMEDY. 

0 

Hot, nonalcoholic drinks and induced perspiration. 


PROPER VENTILATION. 

The main preventive is such good ventilation that the fumes will 
bo at once carried above the workmen’s heads and out of the shop. 
That the “shakes” can be practically eliminated by proper ventila¬ 
tion is shown by some dozen replies to the effect that, though the 
firms represented deal with yellow brass or manganese bronze, by 
reason of ample ventilation no cases have occurred. Several stato 
that although “shakes” used to be common, the trouble has ceased 
since the firm represented has moved into a new, properly ventilated 
foundry, or since suction ventilation has been installed. If “brass 
shakes” occur they are prima facie evidence that the ventilation is 
not adequate. Few plants acknowledge continual trouble from 
“shakes,” most of them replying “rarely,” “seldom,” “only on 
muggy days,” “only on dense days in winter when the windows can 
not be opened,” “beginners only affected,” “only whisky users,” 
etc. One reply states that when unhooded furnaces were used, 15 
per cent of the workers were affected; another, “common during 
winter”; another, “on Monday nights in cold weather”; another, “ 10 
per cent of the men have them on Monday night in winter”; and the 
last acknowledges notable trouble, and says, “Our men had the 
‘shakes’ three times a week on the average before our ventilating 
system was put in; now they average only once a week, and we are 



ESSENTIALS FOR HEALTH AND SAFETY. 


267 


increasing the capacity of the ventilating system in order to eliminate 
them entirely.’’ 

One firm found that after ample ventilation had been provided 
not only did the workers cease to be troubled by “shakes/’ but the 
drunkenness among the workmen was greatly decreased. The 
improvement- is ascribed to the absence of zinc fume, and hence of the 
11 shakes” and the use of alcohol as a remedy. 

To insure good ventilation high roofs are essential. The foundry 
or casting shop should always be either in a high one-story building, 
or on the top floor of a building of more than one story. In either 
case, monitor roofs or similar roofs providing for ample ventilation 
should be used. 

Natural ventilation is usually adequate for removing dust and 
fumes other than zinc fumes from foundries where no alloys high in 
zinc are cast. If yellow brass or manganese bronze are poured, no 
plant should rely on natural ventilation alone, as on dark, cpiiet, 
muggy days, even with all ventilators open, the fumes do not rise 
promptly enough. 

Forced ventilation is advisable in all melting rooms, though the 
warm air always present greatly aids natural ventilation if proper 
hoods are used. Whenever possible, the melting room should be sepa¬ 
rate from the foundry. If the furnaces are in the body of the foundry, 
each should have over it a hood coming down as near to the furnace 
as practicable. If the furnaces are in one end of the foundry, an 
apron should be placed across the whole end in front of the furnaces 
and extending to within about 8 feet from the floor. If the furnaces 
are of the pit type, and permanent hoods do not allow room for lifting 
the pot or do not allow sufficient room for operating the crane, 
swinging or telescoping hoods should be used. 

Any t} r pe of furnace can bo so installed or hooded as to eliminate 
zinc fume. Hence the problem of 11 shakes” need have little to do 
with the choice between different types of furnaces. 

The main trouble is in pouring, and accordingly the pouring floors 
should be amply ventilated. Suction fans are the most common 
means of obtaining forced ventilation. They are put preferably 
in the roof, but are sometimes placed in the side walls, whore they 
should be at least 12 feet from the floor. They must be of ample size 
to keep all fumes lifted above the workmen’s heads. 

With natural ventilation only much trouble is experienced in the 
winter, particularly when cold weather first sets in, for the workmen 
will not open the ventilators if, as a result, the shop will become 
unbearably cold. 

Hence the problem of “brass shakes” resolves itself into one pri¬ 
marily of adequate ventilation for muggy days, but just as truly into 
one of adequate heating for cold days. Probably not one foundry in 


268 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


ton is properly heated in winter, and many an otherwise up-to-date 
foundry will bo found in which stoves or salamanders are used in 
order to keep the molding sand from freezing at night and the molders’ 
hands from being too numb to hold a slick in the daytime. '1 his 
condition exists in spite of the fact that in almost any plant the waste 
heat from the furnaces could doubtless be so applied as to give 
entirely adequate heat. The salamanders are often unhooded, and 
as coke high in sulphur is burned in them, the CO and SO, produced 
are almost unbearable. 

The use of heaters discharging smoke or gas into the foundry is 
prohibited in New York State by recent legislation. 

Aside from the better ventilation, made possible by adequate heat¬ 
ing, and the greater productivity of the men working in a normal 
temperature, it should not bo forgotten that cold sand is a prolific 
cause of “ blows” or other foundry troubles. It may not be easy 
to make a balance sheet show that in the long run the proper heating 
of a foundry will pay, quite aside from the moral obligation of an 
employer to provide proper heat out of regard for the health of the 
workers, but such is certainly the case. The minimum temperature 
on the coldest days should be 50° F. 

MAINTENANCE OF PROPER TEMPERATURE. 

The indirect-air system of heating is giving good results in many 
foundries. 0 Pure air is drawn in by a large blower, is warmed by 
being passed over suitable heating coils or radiators, is forced through 
large pipes overhead or along the walls, and is then delivered to all 
parts of the foundry in large volume but at low velocity. Roof 
ventilators or suction fans remove the air after it lias given up most 
of its heat. This system provides not only heat but also ventilation. 

The air may also be regulated as to humidity, and it is quite possi¬ 
ble that the heating coils might w’ell be replaced in summer by 
some refrigerating device to cool the air. Nearly every foundry 
has to close on a few of the hottest summer days, either because the 
management is unwilling to allow the men to work in temperatures 
liable to cause heat prostrations or because the men refuse to work. 
“Breaking the heat,” as quitting work on account of the heat is 
commonly called, is known in most foundries. The loss occasioned 
by a few days of inaction from this cause might easily pay for the 
cost of the cooling device, to say nothing of the advantage a plant 
known to be cooling its foundry would have in obtaining efficient 
labor. 

Recent legislation in New York requires the maintenance not only 
of proper ventilation but of proper degrees of temperature and 


a See editorial, Heating and ventilation of a large foundry: Iron Age, voL 91,1913, p. 415. 



ESSENTIALS FOR HEALTH AND SAFETY. 


269 


humidity. Suction devices for removing fumes, proper hoods, and 
special means or devices to reduce excessive heat are also required. 

To maintain a reasonable working temperature, a mild blast of 
air, either over the furnace tenders’ heads or directed downward to 
the floor back of them, but not directly on them, when working at 
the furnaces, is necessary in summer with most types of furnaces, 
especially when the furnaces are close together. 

LEAD AND PHOSPHORUS POISONING IN FOUNDRIES. 

Lead poisoning is rare in regular foundry work. Four plants have 
reported cases that are traceable either to the melting of bearing 
bronzes high in lead, or to the refining of lead dross and scrap in 
foundries having smelting departments. 

In one case of lead poisoning the trouble was traced to a lead 
kettle operating on a lower floor, in a room with a low ceiling and 
without adequate ventilation. Thompson® cites several cases of 
lead poisoning among men working in smelting works, and found 
one case of a man working with brass and composition metal con¬ 
taining lead. 

No lead poisoning has been traced to alloys of the normal com¬ 
position having, say, less than S per cent of lead. Great care should 
be used in handling or melting alloys high in lead, or in the use of 
corroded scrap lead. Where conditions prevail that make lead 
poisoning possible, the men should be instructed of its dangers, and 
notices posted or given to the workers, containing such information 
as is given on the following notice, which, in New York State, is 
urnisl\ed free by the State department of labor, and is printed in 
other languages as well as English. 

HOW MEN ARE POISONED BY LEAD. 

(1) Lead is poison to the body. It enters the body mainly through the nose and 
mouth. It may be inhaled as dust or in fumes. It may be swallowed with food or 
saliva (especially if tobacco or gum is put into the mouth with soiled fingers). Or 
it may sometimes be absorbed through the skin. 

(2) When lead gets into the body, it leads among other things to indigestion and 
lead “colic”; to diseases of the heart, blood vessels, and kidneys; or to paralysis of 
the hands, known as “wrist drop.” 

(3) Lead acts upon the body slowly and insidiously. Without knowing your dan¬ 
ger you may be getting some lead poison into your body every day. If you are work¬ 
ing with lead in any one of its many forms, you must therefore use great care so as to 
protect yourself against it. 

pi) On the very first sign of not feeling well, see a doctor or go to a dispensary. Do not 
wait until you are too sick to work. The earlier you go to a doctor, the easier it will be to 
cure you if you are being poisoned by lead. He si re to tell the doctor all about 

YOUR OCCUPATION AND ITS DANGERS. 


a Thompson, W. G. G., Industrial lead poisoning: I’roc. 8th Int. Cong. App. Chem., 1912, vol. 16, p. 53. 




270 


BKASS-FUBXACE PRACTICE IN THE UNITED STATES. 


HOW TO PREVENT LEAD POISONING. 

(1) Always wiwli before eating and, if you work in a factory, before leaving the 
factory.® Remove all dirt from under your finger naila with a brush. 

(2) Never eat in the room in which you work.t> 

(3) Never chew tobacco or gum while working. If you do, the lead dust on your 
fingers and in the air is sure to be swallowed. 

(4) Use overalls when you work. Do not wear your working clothes on the street 
or at home. They may contain lead and poison you and others. 

(5) Respirators are very useful and should always be used when working among 
lead dust or fumes. 

(6) Keep the workroom clean. Do all you can to keep down dust. Do not get 
lead on your hands and clothes any more than you can possibly help. 

(7) Always eat a good breakfast before going to work. Drink plenty of milk. 
Have at least one good movement of the bowels every day. Constipation is a sugges¬ 
tive symptom of lead poisoning. Avoid the use of intoxicants in any form. Their 
use weakens the body and makes it harder for your body to overcome the poison of 
lead. 

(8) Keep clean. Wash with warm water, soap, and nail brush. Take at least one 
full hot bath a week. 

Other notices sent the bureau by foundries describe the symp¬ 
toms—a blue line on the gums, accompanied by debility, loss of 
appetite, sick stomach, headache, colic with constipation, and wrist 
drop preceded by pain or numbness in the forearm. The wearing 
of gloves, the protecting of all cuts and scratches until healed, and 
prompt attention to decayed teeth are also recommended in some 
of the notices. 

A full discussion of industrial lead poisoning and striking photo¬ 
graphs of men afflicted with it are given by Hamilton.® 

No cases of phosphorus poisoning in foundries were reported. 
Where phosphorus is used as a deoxidizer, red instead of yellow* * phos¬ 
phorus may be used, or yellow phosphorus may be plated with cop¬ 
per or wrapped in tea lead. The covering of yellow phosphorus in 
this way is mainly as a preventive of burns from handling the phos¬ 
phorus itself and from explosions when the phosphorus is put into 
the copper or bronze. The precautions against poisoning from phos¬ 
phoric acid fumes are ample ventilation and the compulsory use of 
respirators. 


METALLIC DUST AND SIMILAR IRRITANTS. 

The term ‘‘brass poisoning'' is often loosely used to include not 
only “brass shakes,” but also the troubles arising from inhalation of 
metallic dust from emery grinders, from polishing and bulling devices, 

a In factories the labor law requires employers to furnish washing facilities, including hot water and 
individual towels. 

b The labor law forbids any worker to take food into any part of a factory, shop, or working place where 
lead Is present in “harmful quantities.” 

* Hamilton, A., Investigations on lead troubles in Illinois: Report of Illinois Commission on Occupa* 
tional Diseases, 1911, p 21. 




ESSENTIALS FOR HEALTH AND SAFETY. 271 

etc. Hoffman 0 states in regard to '‘brass shakes/’ or "brass 
founders’ ague:” 

Zinc and other fumes inhaled are the chief causes of this ailment, and it is quite 
probable that the lung injury resulting from the inhalation of fine particles of metallic 
dust is a material contributory cause in brass founders’ ague. 

In few plants, however, are men exposed both to zinc fume and to 
metallic dust; hence the two troubles should be differentiated. 

Hayhurst b more properly terms poisoning from brass dust 
"pseudo-brass poisoning,” and also states that direct toxic effects 
of inhalation of cold metallic brass dust arc mechanical only, and do 
not produce the "shakes,” and that troubles from brass dust fall into 
much the same class as those from iron dust or stone dust, although 
much of the inhaled dust is swallowed, and brass dust may then pro¬ 
duce the poisoning shown by copper, zinc, or lead compounds when 
taken into the stomach. That considerable copper finds its way into 
the system of a grinder is shown by the fact that a grinder’s hair and 
teeth often show a greenish tinge, and his perspiration may also be 
distinctly green. These effects arc not seen in brass meltcrs. The 
evil effects of the inhalation of brass and emery dust have been 
clearly shown by Hoffman c and must be apparent to any one. 
Sand blasting without the use of precautions to prevent the inhala¬ 
tion of the sharp sand particles falls into the same category and is 
reprehensible in the extreme. 

Trouble from these causes may be entirely avoided by the use of 
suction hoods on emery wheels or polishing and buffing wheels. It 
should also be pointed out that the more complete recovery of the 
grindings by an exhaust collecting system goes a long way toward 
paying for its installation. 

Full specifications for the design, construction, and operation of 
exhaust systems for grinding, polishing, and buffing wheels have been 
issued by the New York State Department of Labor. d 

Sand-blast rooms separate from the rest of the foundry, helmets 
for use therein, sand-blast tumbling barrels, and various mechanical 
means for sand blasting without making it necessary to inhale any 
of the dust arc common. The protection in grinding, polishing,* or 
sand blasting may in many cases bo made sufficient so that the use 
of a respirator is not necessary. Unless other means are fully ade¬ 
quate, respirators must of 00111*80 be supplied. The evil effects of the 
dust rising from the knocking out of cores from the castings and from 

o Hoffman, F. L., Mortality from consumption in dusty trades: Bureau of Labor Bull. 79, 1908, p. 602. 

b Hayhurst, E. R., Occupational brass poisoning—Brass founders’ aguei Am. Jonr. Med. Sci., vol. 145, 
1913, p. 724. 

t Hoffman, F. L., loc. cit. 

d See also Foundry, Data sheets 137-143, vol. 41, 1913, May, June, July, and August; Industrial Engi¬ 
neering, vol. 13, 1913, p. 211; Brass World, vol. 9, 1913, p. 102. 




272 BRASS-FURNACK PRACTICE IN THE UNITED STATES. 

tlio preliminary cleaning of castings before cutting or sawing off 
sprues, grinding, or chipping should be mitigated by forced ventila¬ 
tion in the knock-out room, and by frequent sprinkling of tho floor 
with water. Knocking out on gratings helps to reduce tho accumu¬ 
lation of dust. The knock-out gang should bo provided with respi¬ 
rators and goggles. Goggles or eye protectors should always bo sup¬ 
plied to grinders and their use made compulsory. 0 Glass eye shields 
in front of the emery wheels are sometimes used. 6 A pertinent notice 
posted in one plant is as follows: 


SHOP RULES—SAFETY FIRST. 

Do not wear gloves while working around a machine 
while it is in motion. It is dangerous. 

Always wear goggles, which will be furnished you, 
when working cast iron, brass, Babbitt metal, or when 
using emery wheel—they may save tho loss of an eye. 


Plate I shows an illustration used in one firm’s booklet of rules for 
protection against injury. Tho plate shows hooded emeiy wheels 
and the goggles provided for grinders. Dark goggles should bo sup¬ 
plied to furnace tenders. Grinders and chippers may well be pro¬ 
vided with an iron-studded leather apron for protection from 
mechanical injuries when a casting on which they are working slips. 
Gloves should be provided for men handling pig metal. 

Pickling, plating, and lacquering also involve harmful acid spray 
or gases that aro somewhat poisonous. As these arc not operations 
included in foundry work as such, they may be dismissed with tho 
remark that adequate hoods and exhaust ventilation, as well as the 
use of rubber gloves to protect the hands from acid solutions, are 
required. 

PROPER LIGHT IN FOUNDRIES. 

Although modern foundries are being constructed with ample light 
for daywork, many of the older ones are extremely ill lighted. 
Whitewashing c the walls at least twice a year is practiced with great 
success in up-to-date plants, although some foundry owners consider 
it impractical. It is not impractical, however, as those wdio do it 
testify that the expense, when air sprayers arc used, is slight com¬ 
pared to the benefits, as in all modern foundries compressed air is 
available for molding-machine operation. The New York State labor 
law provides that »the inspector may, in his discretion, require 
that walls and ceilings be whitewashed. Some plants make a com- 


° Cameron, W. II., How to prevent blindness among your employees: Foundry, vol. 41,1913, p. 3S2. 
b Pulteney, D. C., Safeguarding factory tools and equipment: Electric Jour., vol. 9,1912, p. 602. 
e See Kitson, A., Foundry and workshop lighting: Metal Ind., vol. 11,1913, p. 3S3. 







BUREAU OF MINES 


BULLETIN 73 PLATE I 



WORKMAN WEARING GOGGLES. NOTE HOODED EMERY WHEEL. 

































ESSENTIALS FOR HEALTH AND SAFETY. 


273 


plcto clean-up whenever they whitewash, all accumulated dust being 
removed from the foundries, and these plants find that the clean 
surroundings are conducive to better and more careful work. Fre¬ 
quent window washing also is of great benefit. It is a common thing 
to see a molder spend ten times as long in taking loose sand from deep 
places in his mold as it would take him were adequate light supplied, 
and he often does as much damage as he repairs. As damp molding 
sand is dark in color, poor light makes unusually deep shadows. 
W indows in the roof, as well as walls that are half or more glass, are 
provided in the most modern plants. To get roof lighting in a build¬ 
ing of more than one story, as well as for better ventilation, the 
foundry should be on the top floor. This location is usually best 
also as regards routing the product, the rough castings going down 
story by story through the finishing process in proper sequence. 

The artificial lighting of the foundry is seldom adequate. Abun¬ 
dant and diffuse lighting is best. A single dirty incandescent bulb 
somewhere near a molding bench is often all that is supplied. Diffuse 
lighting in order to allow the inspection of deep pockets in a mold is 
absolutely essential.' 

For small flasks on bench work, individual Tungsten drop-lights 
or gas arcs may sometimes be adequate, but for large floor work, 
diffuse illumination is required. The soft and diffuse light of the 
mercury arc is considered by some plants to be ideal for such work. 
Flaming arcs are also used, but cast rather more shadow. 

Proper lighting will pay and pay largely in the shape of fewer 
spoiled molds and scrap castings. 

PREVENTION OF BURNS. 

The most serious of all the hazards of the foundry and casting 
shop is that of burns from molten metal. The loss of an eye or even 
of life has come from putting damp metal, a damp skimmer, or damp 
gates into molten metal, and every precaution against such action 
should be taken. Skimming into water is dangerous. Aside from 
cases of this nature, the main danger is from burning the feet or legs 
by metal spilled at the furnaces, in the gangways, or at the mold. 

A shallow pan filled with sand and set into the floor an inch or so, 
but level with it so it will not bo stumbled over, lessens the spattering 
of metal spilled from the lip of a tilting furnace while being poured 
into the ladle. 

In adding zinc (speltering) the zinc should be warmed well beforo 
being put into the molten metal, it should be introduced gradually, 
and the metal should bo slowly stirred. If the zinc be added too 
rapidly, so that it boils, an explosion similar to that from adding 
damp metal may occur and the entire furnace contents bo thrown over 
the melter. 

•H712°—Bull. 73—10-18 


27*4 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 

Gangways must bo kept clear. All workmen should be made to 
realize that skimmers, gates, or anything over which the metal carriers 
might stumble if thrown into the gangway may cost a fellow work¬ 
man’s life or maim him terribly. 

Tho tilling of ladles so full that the metal is likely to slop out or 
running with a ladle of metal is dangerous. Metal carriers should 
understand that when two or more men are carrying a ladle shank 
the ladle must not be dropped no matter what happens. Each 
should hold it until he can tell the others that he is about to set it 
down. If he drops it, he is certain tc be injured and the other men 
are in nearly as much danger. If crucibles in shanks are used as 
ladles, they should be securely wedged in—or, better, held on by a 
clamp—and should be properly balanced so that the center of gravity 
is low. If ladles are carried on overhead trolleys, a gong which may 
be made self-acting should be rung continually to indicate that a 
ladle of molten metal is coming. Crane tracks must be constantly 
inspected for loose bolts. Flasks should be maintained in repair, 
and the flasks should be properly weighted or clamped so that run 
outs will be prevented. 

After all precautions possible have been taken to prevent spilled 
metal, the next essential is that the workmen wear such trousers and 
shoes as will prevent spilled metal from causing serious burns. Fur¬ 
nace tenders, metal carriers, and molders are all liable to burns of 
the feet and legs from spilled metal and run outs. 

Ragged trouser legs, low shoes, lace or button shoes, shoes broken at 
the toe, or congress shoes with gaping tops, all hold spilled metal and 
make serious a spill that would be practically harmless with proper 
pants and shoes. The wearing of congress or molders’ shoes, or else 
asbestos gaiters, over the calf, ankle, and instep should be obligatory. 
Molders’ shoes are bought in large quantity by many firms and sold 
to the workmen at cost. If a man does not wish to buy his own 
congress shoes from a dealer or from the company at cost, and insists 
on wearing out an old pair of lace shoes, he should be forced to weal 
asbestos, canvas,® or leather gaiters supplied by the company. 
Tlie right and the wrong kind of shoes are shown in Plate II, A. 

Asbestos aprons extending to the knee, and trousers faced with asbes¬ 
tos from the knee down, should be supplied to furnace men and metal 
carriers by the company. Care mast be taken that congress shoes 
have a good quality of elastic, so that they do not gap at the top 
before worn out, as bad burns have resulted from hot metal dropped 
into such a gap. 

Bicycle clips are sometimes used by metal carriers to confine the 
trousers at the ankle and prevent them from catching on projections 


a Outerbridge, A. E., Prevention of accidents in the foundry: Iron Age, vol. 92,1913, p. 772. 





BUREAU OF MINES 


BULLETIN 73 


PLATE II 



A. RIGHT AND WRONG KIND OF SHOES FOR FOUNDRY WORKERS. 



/»’. SHOE THAT ALLOWED WEARER TO SUFFER A SEVERE BURN FROM HOT METAL. 















ESSENTIALS FOR HEALTH AND SAFETY. 


275 


and causing a fall. If clips are worn, care must be taken that no 
pockets are formed by the folds that will retain molten metal spilled 
into them. 

Some good rules for the avoidance of burns appearing in a safety 
booklet given to each employee in the foundry of one firm are pre¬ 
sented below: 

Rules for 'preventing bums. 

Reporting accidents. —In case of injury, no matter how slight, even a slight cut or 
burn, report at once to your foreman. Sometimes a slight cut or burn will result in 
blood poisoning if neglected. 

Examine ladle and skimmer. —Examine carefully the ladle or skimmer before using 
to see that it is not damp or wet. A damp or wet ladle may cause an explosion. 

Filling ladles too full. —Do not fill your ladle too full, as you are liable to spill its 
contents and receive serious burns. 

Catching metal. —In catching metal from tilting furnaces men must be careful to 
handle their ladles in such a way as to cut the stream in toward the furnace. 

Turn out to the right. —In gangways always turn out to the right, and when you meet 
a man carrying a ladle of hot metal give him plenty of room. 

Foot near mold in pouring. —In pouring metal into molds be careful not to have the 
foot too near the mold; also be careful not to get into such a position as to make it 
hard to get away quickly should the metal break through the mold. Many serious 
burns of the feet have been caused in this way. 

Explosion of gases. —When pouring large flasks or molds, the gas must always be lit 
to save an explosion that is liable to occur from the dampness of the sand in the mold. 

Pouring hot metal or slag on damp ground. —Great care must be taken not to pour 
or spill hot metal or slag on the damp ground or in vessels in which there is water. 
If you do, an explosion may occur and you may be seriously injured. 

Obstructing gangways. —Workmen are forbidden to leave in the gangways weights 
or other material over which men may stumble and fall. 

Don’t run with a ladle. 

Don’t drop a ladle. 

Keep pants repaired. —Workmen must keep their pants repaired from the knee 
down and around the bottom, so that the legs and feet will be protected from the 
hot metal if it spills. 

Congress shoes. —All foundry men must wear congress shoes.' (Many men wearing 
lace shoes have had their feet seriously burned because they could not take the shoes 
off quickly enough or because the hot metal burned through the open part where the 
laces cross.) 

Inspection of crane tracks. —The crane tracks must be inspected every two weeks 
for broken or loose bolts. 

The firm issuing the rules quoted also issues at intervals a safety 
bulletin to its employees. A significant quotation is as follows: 
“When caution becomes a habit, there will be few accidents.” 

In one issue of the bulletin the firm mentioned reproduced the 
photograph shown in Plate II, B. The plate shows a shoe the wearer 
of which suffered a serious bum, causing the loss of 60 days’ time. 
The only place at which the shoe is burned is at the little toe. Had 
this been a good, strong shoe the injury would have been slight, but 
owing to the broken condition of the shoe, the metal poured in the 



276 BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


break all across the top of the foot, seriously burning all the toes. 
As the shoo was of the button type, the employee could not remove 
it quickly, as he could have clone had he worn congress shoes. 

No amount of ordinary notices or verbal warnings can be as im¬ 
pressive as such an illustration as this presented to employees. 

Olio foundry posts the following well-worded notice: 


WARNING. 

Most of the serious accidents that have recently 
happened in this foundry would have been prevented 
if proper shoes had been worn. 

The company will furnish such shoes at cost if de¬ 
sired, but will be quite as well pleased if employees 
will purchase them elsewhere. 

The point is: 

Wear molders’ shoes and avoid danger. 


Asbestos gloves should be provided for furnace tenders and metal 
carriers. 

Great care should be taken in the use of gasoline for drying molds 
or green sand cores. Gasoline torches for “skin drying’’ should be 
used with caution. Gasoline torches, or large torches using fuel oil, 
should not be filled in the foundry, or by the users, but in a place 
away from flame and by the stock keeper. 

In one instance the oil in a large torch was used up, and, rather 
than go to the stock room for more, a molder dumped gasoline into 
it from a small torch. An explosion resulted that set the clothes 
of two workmen afire. One of them ran down the gangway, thus 
fanning the flame; the other was caught and rolled into a pile of 
molding sand. The first was badly burned, but the second escaped 
with only slight burns. 



ESSENTIALS FOR HEALTH AND SAFETY. 


277 


TREATMENT OF BURNS. 

Neglect of slight burns may result in blood poisoning; hence even 
the slightest burn should receive prompt attention. One notice 
posted in regard to treatment of burns follows: 


NOTICE. 

REGARDING BURNS FROM MOLTEN BRASS. 

If the burn is slight, wash it first with a warm solu¬ 
tion of a mixture of 50 parts of water, containing 2 per 
cent Carbolic Acid, and 50 parts of a strong solu¬ 
tion of Sodium Carbonate. After the pain has sub¬ 
sided, apply a bandage saturated with a mixture of 80 
per cent strong Lime Water and 20 per cent boiled 
Linseed Oil. After the blister that forms has broken 
or been reduced, the burn should be dressed with 
Hydrogen Peroxide diluted with one-half water, and 
the wound will heal. 

If the burn is serious, call a physician, and, pending . 
his arrival, apply the Carbolic Acid, and leave the rest 
of the treatment to the doctor. 


The New York State law now specifies as follows: 

There shall be in every foundry, available for immediate use, an ample supply of 
lime water, olive oil, vaseline, bandages, and absorbent cotton, to meet the needs 
of workmen in case of burns or other accidents; but any other equally efficacious 
remedy for burns may be substituted for those herein prescribed. 

An emergency case with suitable supplies for the first treatment 
of burns should be in every melting room, and the foreman should 
be taught how to use the supplies. This advice holds even if there 
is an emergency hospital connected with the plant, as preliminary 
treatment should not be delayed. 

DANGER FROM MOVING MACHINERY. 

The safeguarding of moving machinery to prevent injury is as 
essential in the foundry as in the machine shop. As the foundry 
proper seldom contains much machinery, the main things to be safe¬ 
guarded are band saws, sprue cutters, emery wheels, elevators, hoist¬ 
ing shafts, core-sand mixers, and, in particular, the woodworking 
machinery of the pattern shop. 







278 BBA88-FURNACE PRACTICE IN THE UNITED STATES. 


One foundry visited used an unguarded bund saw, but the manager 
promised to guard it at once. All belts and gearing should bo 
guarded, whether in the power house, sand-mixing room, grinding 
room, or foundry proper. 

Notices should be posted and employees warned regarding sus¬ 
pended crane loads, and cranes should bear a gong to be rung when¬ 
ever tlio crane is carrying a load. 

DANGER SIGNALS. • 

At any places where danger exists, such as at the door between the 
melting room and the foundry where a workman may be suddenly 
met by a metal carrier with a ladle of hot metal, if the layout of 
equipment can not be so planned as to give a clear view, largo red 
signs bearing in English, and in the language of any foreign work¬ 
men employed, the legend “ Danger —Look out for the metal car¬ 
rier,” or “Look out for-,” whatever the hazard may be. 

There are times in all foundries when alterations have to be made 
while the plant is running, when safety devices have to be temporarily 
removed for repair, or when workmen may be temporarily doing over- 
headyvork, so that tools, etc., are liable to be dropped. The approaches 
to places where such temporary hazards exist should be marked by 
red flags, to indicate danger. Notices should be posted of this nature: 
“Caution —Red on machines and appliances means Danger.” 
Repair work requiring men to work above furnaces should not bo 
done while the furnaces are running, or while they arc hot. 

Great care should be taken that flasks and castings stacked on 
trucks or other materials are securely piled, so that they may not fall 
on workmen. Broken legs or more serious injuries may result from 
neglect of this precaution. 

Boards with nails in them should not be allowed to lie where they 
might be stepped on. Wrestling, scuffling, throwing sand, or horse¬ 
play of any sort is dangerous and should be prohibited in the foundry, 
even outside of working hours. 

BATHING. 

As foundry work, even with all reasonable precautions, is of a 
dusty nature and induces perspiration, suitable bathing facilities 
should be provided. These should not consist merely of a pail of water 
drawn from a faucet, but should embrace enough individual basins, 
or sinks, so that each man may wash without having to wait long for 
his turn. Soap, hot water, and individual towels are essential. 
These are all required by New York State laws. Illinois laws specify 
also nail brushes and nail cleaners, and one water spigot to every six 
employees, and make it illegal for the workmen to eat without 
washing their face and hands and cleaning their nails. Moreover, 



ESSENTIALS FOR HEALTH AND SAFETY. 


279 


the Illinois laws require shower baths sufficient to allow each employee 
a shower bath once a day, when the inspector deems them essential. 

The provision of bath towels is also specified. The Illinois laws 
further specify that proper working clothes must be provided without 
cost to the employee and must be kept reasonably clean by the 
employer. On visiting some Illinois foundries, the author found that 
this provision of the law was not being rigidly enforced, although 
several of the larger foundries were willingly complying with it. 

The New York laws require that suitable provision be made for 
drying the working clothes of foundry employees. Separate 
lockers for street and working clothes are provided by some plants, 
and are advisable. If such lockers are not used, one well-ventilated 
locker for each employee should be provided. 

The most progressive plants allow the workers sufficient time to 
wash, on company time, at noon and night. The following notice, 
taken from a booklet given to the employees of one firm, gives good 
advice, and might well be posted in all shops. 


HEALTH. 

Foundry employees are particularly warned of the 
danger to their own health of leaving the molding 
rooms and exposing themselves to the weather until 
after they have cooled off and clothed themselves prop¬ 
erly. A good practice to follow before leaving is to use 
the wash rooms provided. 


EATING IN THE FOUNDRY. 

Both New York and Illinois absolutely prohibit eating in the 
foundry. New York requires that suitable quarters be maintained 
to enable the workers to take their meals elsewhere in the establish¬ 
ment. Illinois specifies lunch rooms wherever practicable. 

Eating amid the dust and fumes of the foundry is plainly objection¬ 
able, as is the handling of chewing tobacco without washing the 
hands. The practice of allowing a period of 10 or 15 minutes in the 
middle of the morning for the eating of food brought into the foundry, 
which is a relic of days when the hours of labor were much longer, 
and is still common, especially in some parts of the Middle West, is 
reprehensible, as it does not allow time enough for the workers to go 
to and from the lunch room, and means that food is eaten amid dust 
and with dirty hands. Such a recess is hardly necessary with 
modern hours of labor, but, if given, should be long enough to allow 
washing and the use of the lunch room. 









280 BRASS-FURNACE PRACTICE IN T1IE UNITED STATES. 

If washing before eating is required by law, the employer is of 
course able to enforce such a rule. In States where there is no such 
legislation some employers report far less difficulty in enforcing such 
a rule than they had imagined would be the case. 

w O 

MISCELLANEOUS EQUIPMENT AND PRECAUTIONS. 

The following should be provided in every foundry: Respirators, 
goggles, and leggings to those whose work requires them; an adequate 
number of wash basins; hot and cold water; soap; nail cleaners; 
individual towels; shower baths; well-ventilated individual lockers; 
dressing rooms; lunch rooms provided with sufficient tables and 
benches to accommodate all workers. 

The weekly washing of the work shirt and trousers of each em¬ 
ployee at company expense might also well be provided for. Time for 
washing at noon and night should be allowed. There should be an 
absolute prohibition against eating in the foundry' or without washing. 
The supplying of hot coffee and milk at cost is advisable, and in many 
localities remote from restaurant facilities, or where those near the 
plant are of low grade, it is wise to have a company lunch room 
where hot meals may be obtained at cost by those who do not wish 
to carry lunches or prefer a hot meal. 

It should be unnecessary to mention that all toilets and urinals 

•/ 

should be kept clean and properly' disinfected, and should be far 
enough removed from the workrooms so that the offensive odors will 
not be present in the workrooms. A surprisingly large number of 
foundries, however, neglect these elemental sanitary' precautions. 

As the heat of the foundry and the perspiration induced require 
the drinking of a large quantity of water by the workmen, particu¬ 
larly the furnace tenders, the purity of the water supply' must be 
beyond question. Furnace tenders and casters who use alcohol to 
excess almost always have digestive or intestinal troubles in hot 
weather, and although these probably can not be entirely eliminated 
from the heavy drinkers, a pure water supply' will lessen them. One 
plant reports that colic or cramps were very' common with its work¬ 
men until the water was filtered and the method of its cooling 
changed from direct to indirect icing. The water should not be 
cooler than 4S° F.° Sanitary bubbling fountains cooled without 
direct contact with ice and fed by' pure water are necessary'. If the 
water supply is not beyond question, or can not be made so by filter¬ 
ing, use should be made of bottled spring water or distilled water. 

O Toliuan, W. U., and Kendall, L. B., Safety, 1913, p. 17. 




ESSENTIALS FOR HEALTH AND SAFETY. 


281 


MEDICAL ATTENDANCE AND INSPECTION. 

Illinois requires that brass-foundry workers be examined once a 
month, and preferably once a week, by a regularly licensed physician, 
and a report made by him to the State board of health in regard to 
any workers suffering from occupational disease. Such workers may 
not be kept at work but must be transferred to work at which expo¬ 
sure to the factors causing such disease is not involved. 

An interesting case in one Illinois plant might be taken to show 
that foundry work is not necessarily unhealthful. A man working 
in the paint shop was found on one monthly inspection to be in the 
first stages of lead poisoning. He was transferred to the brass 
foundry (through an error), and at the next monthly inspection it 
was found that he was not only free from lead poisoning but had 
gained 20 pounds in weight. 

A monthly medical inspection is a most sensible provision. A few 
of the larger manufacturing plants in other States, whose work 
includes casting or founding, accomplish the same ends more or less 
thoroughly by having a company physician, either permanently in 
residence at the plant, or making periodical visits. Some maintain 
company hospitals, with a graduate nurse in attendance. At the 
hospitals first aid is given in case of injury and treatment is made for 
colds, sore throats, or other minor ailments. At some of the hos¬ 
pitals the equipment is so complete that in an emergency major 
operations may be made. 

Although a fairly large number of employees is necessary to make 
a plant hospital absolutely demanded, there is no good reason why 
many plants too small to support a hospital room should not be able 
to arrange for the establishment of a cooperative hospital room sup¬ 
ported by several manufacturing plants situated near together. By 
thus dividing the expenses three or four adjoining plants could obtain 
the advantages of a plant hospital for their employees without involv¬ 
ing any noticeable financial burden. 

PROPER PERIOD OF LABOR. 

No definite information as to the hours of labor was requested in 
the list of questions issued, but a statement as to the number of hours 
per day the furnaces were in operation was requested. In some 
plants the furnaces are not run all the working day, and in others 
they are started early. It is rather common practice to have the 
night watchman light coke or coal fires. Out of 205 replies to the 
question on hours per day per furnace, 25 report a run of more than 
10 hours; 1 runs 24 hours in shifts, 05 report a 10-hour run, and 114 
report a run of less than 10 hours, a 9-hour run being the most com¬ 
mon, although there are a number of plants running on an 8-hour 


282 


BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


basis. Nearly all of the 25 plants reporting a run of more than 10 
hours use coke or coal furnaces, and it is probable that very few of 
these have over 10 hours of labor. The average time of running the 
furnace, as specified in all the replies, is well under 9$ hours. It is 
therefore estimated that about half the plants reporting work 10 
hours and about half either 9 or 8 hours. 

FATIGUE AND OVERSTRAIN. 

Rupture used to he common among molders and casters, hut the 
advent of cranes and mechanical hoists has almost done away with 
this ailment. No plant doing heavy work requiring large copes or 
the handling of large crucibles can afford to be without adequate 
crane service. One plant posts the following notice: 

Don’t try to lift on or off a cope that is heavy for you because you are in a hurry. 
Use the crane, call sufficient help, or call the foreman’s attention to it. 

Hayhurst a reports as follows: 

Workmen complain that they are now required to do from one-half to double again 
as much as they were wont to do 20 years ago. * * * There is considerable com¬ 
plaint among many brass molders of the constant physical and mental strain required 
at the present day. A foreman or other expert sets a pace on a certain class of work 
for a few hours’ or a day’s time, then men are compelled to keep up to this record 
daily. Correction: Limit the number of standard flasks or molds or their equivalents 
which a man should be expected to turn out in a day. 

However, this condition is rare. Proper management holds that 
the maximum production possible by the use of improved appliances 
and scientific methods of time study, coupled with constant instruc¬ 
tion of the men in the best and easiest ways of doing the work, is 
desirable, from the point of view, of both employer and employee. 
Waste of a workman's time through failure to give him full instruc¬ 
tions as to the best way to do the work Is as bad a violation of the 
principles of conservation as waste of fuel or metal. 

Speeding, or pace-setting, used blindly to set a rate of production 
that is arbitrarily required, without giving the men proper equipment 
and constant instruction as to how to accomplish the task, is cer¬ 
tainly reprehensible. However, time study and the devising of ways 
of eliminating waste motions often show that a man’s production may 
be doubled and at the same time his hours of labor reduced and his 
physical exertion lessened, lieadwork by the management being sub¬ 
stituted for much of the old handwork by the worker. The result 
may be an increase in wages for the workman in proportion to his 
efficiency. Hence, any arbitrary limiting of production is a step 
backward rather than forward. Ilayhurst’s suggested correction is 

a Hayhurst, E. R., Investigation of the brass-manufacturing industry of Chicago: Report of Illinois Com¬ 
mission on Occupational Diseases, l&ll, pp. 79, SI. 




ESSENTIALS FOR HEALTH AND SAFETY. 


283 


impractical, as there is no such thing as a standard flask or mold, all 
patterns varying in the amount and difficulty of the labor required. 
1 his suggestion was not incorporated in the Illinois law. The basic 
principle of the suggestion mentioned above, that of not forcing or 
inciting a workman to do more than he can with complete safety, is 
beyond reproach, though the suggestion was incorrectly worded. 

Blakey a deals with this subject very sensibly when ho says: 

Fatigue is one of the most important subjects which arises in the problems connected 
with industrial disease, because of its connection with the question of how many 
hours should constitute a day's work. This problem will never be determined scien¬ 
tifically or satisfactorily until adjusted according to the principles of physiological 
fatigue. Certainly everyone will admit that the capability for work varies according 
to the constitution, the age, the sex, the modes of life, and some allowance must be 
made for the individual capacity for work. On the other hand, no two occupations 
are identical in their demands upon physical or mental power. The man who works 
in intense heat should not have the same number of continuous hours as a carpenter 
at the bench; the textile-factory operator, who at her machine watches ] 6 to 18 needles 
for broken thread, with the severe strain thus imposed, should not have the same work¬ 
ing schedule as the girl who sells goods behind a counter. Surely the hours of toil 
should be proportional to the nature of the work and as to its fatiguing character. 
No arbitrary rule can be made which will meet these demands. 

One plant reports that in hot weather they “ spell off” their furnace 
tenders, so as to reduce the danger of heat prostrations or weakening 
of the system. This precaution is admirable. 

Much can be done toward eliminating fatigue and overstrain by the 
maintenance of proper shop conditions. It is quite possible to put 
up many more flasks a day in a shop that is well lighted and venti¬ 
lated, kept cool, and in which good sanitation prevails, and with 
instructions on how to eliminate waste motions, than can be pro¬ 
duced from the same pattern in a hot, poorly ventilated, poorly 
lighted, unsanitary shop in which the men are driven on by unscien¬ 
tific u speeding.” 

Much can also be done by fitting the man to the job—that is, by the 
exercise of common sense and a little applied psychology in the hiring 
of men and in assigning them to various forms of work. Men of slight 
physique, those liable to pulmonary troubles, or those of such nervous 
and excitable temperament that they are likely to lose their head in 
an emergency and spill molten metal on themselves or their fellow- 
workmen, should not be employed as furnace tenders, casters, or 
metal carriers. Yet these same men may, from their nature, be the 
most efficient workers at bench molding, core making, or other 
employments around the plant. 

The work of Munsterberg is 6 of great interest in this connection. 


a Blakey, II. B., Occupational diseases: Bull. Ohio State Board of Health, 1913 (reprint), p. 6. 
b .Munsterberg, II., Psychology and industrial efficiency, 1913. 




284 


BBASS-FURNACE PRACTICE IN THE UNITED STATES. 


EMPLOYMENT OF WOMEN AND CHILDREN. 

The foundry industry is practically free from reproach on the score 
of the employment of women or children. 

Child labor in foundries is rare and is usually confined to time boys 
and boys who sort chills, core wires, etc. No boy should bo allowed 
to work in a location exposed to zinc fumes, furnace gases, or at 
dusty work, without proper precautions being taken to lay the dust 
and to prcfvide respirators. Women workers are found only in the 
core rooms. On small, light cores their dexterity and care make 
them far better workers than men or boys. Moreover, if the core 
rooms in which the women are employed are—as is almost always 
and should always be the case—separate from those in which male 
help is employed, if the rooms are well lighted, ventilated, and 
heated and freo from furnace fumes or gases from the baking cores, if 
the women are not allowed to handle heavy core boxes or core plates, 
if stools are provided for their use, and if ample separate toilet facili¬ 
ties are provided, there seems to be no reason why core making 
should be any more detrimental to the health of women than clerking 
in a department store. 

Most foundries employ women core workers for an 8-hour day 
only, and they come to work a little later and leave a little earlier 
than the men so as to allow the women to avoid the crowded transpor¬ 
tation period. Their lunch hour is commonly different from that of 
the male workers. Many plants provide neat caps and aprons which 
are kept clean by the management. 

POSTED NOTICES. 

Of 230 firms represented in replies, 145 post no notices and do not 
mention giving verbal instruction to workmen in regard to hazards. 
Most of these state that there is no trouble from 1 ‘shakes ,” either 
because no high-zinc alloys are melted, or because of ample ventila¬ 
tion. Several state that few men are employed, these well under¬ 
standing the hazards; others state that no special hazard exists,' 
or that no minors or foreign laborers are employed, the hazard of 
bums being neglected in such plants. 

Sixty replies state that no notices are posted, but full verbal 
instructions are given, particularly to new men. About 25 post 
notices, 10 of these referring only to those notices required by the 
State laws. Fifteen post special notices, mainly giving such cautions 
against injuries as warnings against being under suspended crane 
loads, or cautions as to burns, with no mention of “brass shakes.” 

Not ices ought to be posted in all foundries or casting shops warning 
against all hazards from mechanical equipment, from burns, against 
eating in the foundry or eating without washing, against exposure 
to cold air without first cooling off, and, wherever the possibility of 


ESSENTIALS FOR HEALTH AND SAFETY. 


285 


“brass shakos” or lead or phosphorus poisoning exists, against those 
troubles. The notices should be in all the languages of the workers 
employed. Red danger signs or flags should be used at points where 
permanent or temporary hazard exists. 

Notices should be brief and conspicuous. A typewritten notice 
in an obscure corner is of no avail. Short, common words, and an 
unstilted style, so that the men will not only understand the notice, 
but be impressed by it, should be used in writing notices. It is better 
to state: “If you disregard this precaution you will be injured,” than, 
“you may be injured.” 

However, notices are by no means sufficient, and no manager 
should rest serene with a mere posting of them. Constant instruction 
is necessary by word of mouth to all employees, not only at the time 
of employment, but constantly, as to all general hazards and those 
special ones to which their particular work is subject. 

Booklets describing all hazards and giving instructions for their 
avoidance, explaining precautions against occupational diseases 
possible in the plant, and discussing general sanitation both in and 
out of the plant, describing accidents that have occurred in the plant 
or in similar ones, and explaining how they might have been avoided 
may well be distributed to all employees. The booklets should be 
printed in the language of the recipient. Publications of the Amer¬ 
ican Museum of Safety, of the National Founders’ Association,® and 
of some of the metal-trades associations on the points mentioned 
might also be distributed. 

A most efficacious method is now and then to place a personal 
letter, or a special notice or bulletin pertaining only to the hazards 
of the recipient’s particular work, in his pay envelope. 

A “safety” bulletin board on which arc displayed besides the usual 
notices, clippings from articles on safety which deal with the foundry, 
curves showing the ratio of accidents to men employed in the various 
departments during the past week, so placed that all workers have 
to pass it on the way to work, is used in several plants. The author 
chanced to visit one of these just after some new curves and clippings 
had been posted, and watched to see whether the workmen who 
passed it glanced at it or not. Out of half a dozen men who went by 
it while it was watched, not one failed to pause and read what was 
posted there. 

GENERAL MEANS OF PROMOTING SAFETY. 

Each man in the employ of a plant should be made to realize that 
the motto of the plant is “Safety first,” and that it is his individual 
duty to look out for the health and safety, not only of himself, 
but of his fellow workmen. Careless employees should bo kindly 
warned, and habitually careless ones should be discharged. 


a See editorial article, Foundry, vol. 42,1914, p. 49. 




28t) BRASS-FURNACE PRACTICE IN THE UNITED STATES. 


Suggestions from the workmen for the guarding of hazardous 
places, or for safer methods, should ho invited and used. 

It is well to have weekly meetings of the foremen at which accidents 
or narrow escapes that have occurred are discussed and plans are 
made for the prevention of similar accidents. A lecture on sanitation, 
occupational diseases, and methods of giving first aid to the injured 
should be given each year to the foremen by a good physician. 

There should be a safety committee whose duty it is to make 
a tour of the plant each week to inspect all hazardous places and 
to investigate occupational diseases and sanitation. This committee 
should take suggestions from any source from which it can get them 
and should report on all accidents or narrow escapes. The member¬ 
ship may include the plant manager, superintendent, some of the 
foremen, and one or two of the older workmen. 

WELFARE WORK. 

Whether a firm need go beyond the elimination of occupational 
diseases, the reduction of hazards, and the maintenance of sanitary 
conditions, into what is commonly termed “welfare work” will not 
be discussed here. There are, however, certain projects for the bet¬ 
tering of housing conditions, public baths, establishment of libraries, 
public parks, band concerts, etc., that are properly municipal affairs, 
but so vitally affect the physical and mental well-being of the 
employee in his life outside the factory gates that they may often be 
properly supported by the members of the firm, or, in some instances, 
receive subscriptions from company funds. The sanitation, water 
supply, and transportation facilities of the parts of the city or town 
affecting the employees of the company should be subject to scrutiny 
by its officials, and all proper steps should be taken to improve them. 

SUMMARY OF ESSENTIALS FOR HEALTH AND SAFETY. 

The employees of the modem brass foundry ought to find that the 
shop in which they work is properly lighted, heated, and ventilated 
and provided with pure water; that proper toilet and bathing facili¬ 
ties are provided and company time allowed for their use; that dust 
and fumes are so eliminated that the hazard of occupational disease 
is not present; that all machinery or appliances, such as saws, emery 
wheels, and sand blasts, are properly safeguarded; that the hours of 
labor and its character are reasonable; that medical attention is 
available, and that the motto of the foundry in word and spirit is 
“Safety first.” 

With such conditions there is no reason why the brass industry 
need be dangerous to health and safety, and as the worker’s efficiency 
is dependent on his vitality, there is not one of the items named that 
will not pay the employer in dollars and cents. 



BRASS-FURNACE PRACTICE IN THE UNITED STATES. 287 


ACKNOWLEDGMENTS. 

It is a matter of regret that the necessity of obtaining the data 
for this bulletin in confidence prevents the specific acknowledgment 
of the aid of all who have so freely and so courteously supplied the 
information used in its preparation and have thrown open their 
plants for inspection. Especial thanks are due to the officers and 
members of the American Institute of Metals for their cordial coop¬ 
eration, both personal and official, and to Prof. W. D. Bancroft of 
Cornell University, whose cooperation and advice have been both a 
service and an inspiration. 


PUBLICATIONS ON MINERAL TEC HNOLOGY. 


The following Bureau of Mines publications may bo obtained free 
by applying to the Director, Bureau of Mines, Washington, D. C. 

Bulletin 3. The coke industry of the United States as related to the foundry, by 
Ric hard Moldenke. 1910. 32 pp. 

Bulletin 12. Apparatus and methods for the sampling and analysis of furnace 
gases, by J. C. \Y. Frazer and E. J. Hoffman. 1911. 22 pp., 6 figs. 

Bulletin 16. The uses of peat for fuel and other purposes, by C. A. Davis. 1911. 
214 pp., 1 pi., 1 fig. 

Bulletin 19. Physical and chemical properties of the petroleums of the San Joaquin 
Valley, Cal., by I. C. Allen and W. A. Jacobs, with a chapter on analyses of natural 
gas from the Southern California oil fields, by G. A. Burrell. 1911. 60 pp., 2 pis., 
10 figs. 

Bulletin 22. Analyses of coals in the United States, with descriptions of min * and 
field samples collected between July 1, 1901, and June 30 1910, by N. W. Lord, with 
chapters by J. A. Holmes, F. M. Stanton, A. C. Fieldner, and Samuel Sanford. 1913. 
1200 pp (in two parts). 

Bulletin 42. The sampling and examination of mine gases and natural gas, by 
G. A. Burrell and F. M. Seibert. 1913. 116 pp., 2 pis., 23 figs. 

Bulletin 45. Sand available for filling mine workings in the Northern Anthracite 
Coal Basin of Pennsylvania, by N. H. Darton. 1913. 33 pp., 8 pis., 5 figs. 

Bulletin 47. Notes on mineral wastes, by C. L. Parsons. 1912. 44 pp. 

Bulletin 53. Mining and treatment of feldspar and kaolin in the southern Appa¬ 
lachian region, by A. S. Watts. 1913. 170 pp., 16 pis., 12 figs. 

Bulletin 64. The titaniferous iron ores of the United States, their composition and 
economic value, by J. T. Singewald, jr. 1913. 145 pp., 16 pis., 3 figs. 

Bulletin 65. Oil and gas wells through workable coal beds; papers and discussions, 
by G. S. Rice, O. P. Hood, and others. 1913. 101 pp., 1 pi., 11 figs. 

Bulletin 70. A preliminary report on uranium, radium, and vanadium, by It. B. 
Moore and K. L. Kithil. 1913. 101 pp., 4 pis., 2 figs. 

Bulletin 71. Fuller’s earth, by C. L. Parsons. 1913. 38 pp. 

Technical Paper 1. The sampling of coal in the mine, by J. A. Holmes. 1911. 
18 pp., 1 fig. 

Technical Paper 3. Specifications for the purchase of fuel oil for the Government, 
with directions for sampling oil and natural gas, by I. C. Allen. 1911. 13 pp. 

Technical Paper 8. Methods of analyzing coal and coke, by F. M. Stanton and 
A. C. Fieldner. 1913. 42 pp., 12 figs. 

Technical Paper 14. Apparatus for gas-analysis laboratories at coal mines, by 
G. A. Burrell and F. M. Seibert. 1913. 24 pp., 7 figs. 

Technical Paper 32. The cementing process of excluding water from oil wells, as 
practiced in California, by Ralph Arnold and V. R. Garfias. 1912. 12 pp., 1 fig. 

Technical Paper 38. Wastes in the production and utilization of natural gas, and 
means for their prevention, by Ralph Arnold and F. G. Clapp. 1913. 29 pp. 

288 


PUBLICATIONS ON MINERAL TECHNOLOGY. 


289 


Technical Paper 39. The inflammable gases in mine air, by G. A. Burrell and 
F. M. Seibert. 24 pp. f 2 figs. 

Technical Paper 41. Mining and treatment of lead and zinc ores in the Joplin 
district, Missouri, a preliminary report, by C. A. Wright. 1913. 43 pp., 5 figs. 

Technical Paper 43. The influence of inert gases on inflammable gaseous mix¬ 
tures, by J. K. Clement. 1913. 24 pp., 1 pi., 8 figs. 

Technical Paper 50. Metallurgical coke, by A. W. Belden. 1913. 48 pp., 1 pi., 
23 figs. 

Technical Paper 54. Errors in gas analysis due to assuming that the molecular 
volumes of all gases are alike, by G. A. Burrell and F. M. Seibert. 1913. 16 pp. 

Technical Paper 60. The approximate melting points of some commercial copper 
alloys, by H. W. Gillett and A. B. Norton. 1913. 10 pp., 1 fig. 


44712°—Bull. 73—16-19 































































































INDEX 


A. 


Page. 


Air supply of furnace, increase of, effect of... 214 


preheating of. 224 

methods of. 225 

Alioys, copper-zinc, boiling points of. 128 

curves showing. 129 

melting of, speed of, conditions gov¬ 
erning. 122 

number of. 244,247 

pouring temperature of. 131 

curves showing. 129 

quality of, from open-flame furnaces. 197 

standardization of. 244 

vapor pressure of. 126 

curves showing. 127 

volatilization of. 130 

wastes in manufacture of. 244 

high-zinc, charge for, analysis of. 48, 

50.52.54.56.58.60.62.64.66.68 
composition of. 48, 

50.52.54.56.58.60.62.64.66.68 
furnaces for, details of. 48, 

50.52.54.56.58.60.62.64.66.68 
melting of, details of..48-69 

fuel consumed in. 48, 

50,52,54,56,58,60,62,64,66,68 


loss in 


49, 


51.53.55.57.59.61.63.65.67.69 
speed of. 49, 

51.53.55.57.59.61.63.65.67.69 
tow-zinc, charge for, analysis of. 46, 

48,50,52,54,56,58,66, 68 

composition of. 46, 

48,50,52,54,56, 58,66,68 

furnaces for, details of. 46, 

48,50,52,54,56,58,66,68 

melting cf, details of.48-69 

fuel consumed in. 46, 

4S, 50,52.54,56,58,66,68 


loss in. 47, 

49,51,53,55,57,59,61,63,65,67,69 

speed of. 47, 

49,51,53,55,57,59,61,63,65,67,69 


relative value of. 244 

See also Brass, Bronze. 

American Institute of Metals, acknowledg¬ 
ment to. 287 

cooperation of. 13 

Analyses in foundry work, need of. 248 

Aprons for molders, use of. 274 

Arsenic, traces of, in brass furnace fumes. 259 

Ashos, recovery of fuel from. 231 

recovery of metal from. 237 

Atomization, use of air for. 189 

use of steam for. 189 

disadvantages of. 189,190 


Atomizing burners. See Burners, atonlizing. 


Babbitt metal, composition of. 94 

Bailies, types of. 194 

Ball mill, use of, in concentrating wastes... 236,242 

Bancroft, \V. D., acknowledgment to. 287 

Barnes, E. A., on need of oil meter. 221 

on utilization of waste heat. 226 

Barnhurst, II. R., on use of powdered coal.. 212 

Bartley, J., on life of crucibles. 166 

on round and square furnaces. 176 

on thickness of coko in furnace. 176 

Bassett, W. II., on effects of zinc fumes. 262 

on pouring temperature of yellow brass.. 131 

on use of chlorides as fluxes. 142 

on volatization of zinc. 130 

Bauer, O., on absorption of gases in copper.. 146 

Becker, J., on use of city gas. 182 

Bell metal, composition of. 245 

Bengough, G. D., on volatilization of zinc_ 128 

Bensel, F., on electric brass furnace. 211 

on air for atomization. 189 

on metal from open-flame furnaces. 195 

Best, W. N., on Mexican oil fields. ISO 

on oil-fired reversing furnace. 223 

Blakey, H. B., on fatigue of workmen. 2S3 

Bone, W. A v on surface combustion.215,216 

Booth, W. II., on efficiency of natural-draft 

pit furnaces. 31 

on efficiency of pit oil furnaces. 34 

on tilting, open-flame oil furnaces. 37 

Borings, briquetting of. 233 

melting of, loss in. 233 

removal of oil from. 233 

utilization of. 232 

Bragg, C. T., on electric furnaces. 211 

Brannt, W. T., on coke furnaces. 20 

Brass, composition of. 72 

half yellow and half red, composition of.. 246 

manufacture of, waste in. 247 

melting of, loss in.10,73,111 

importance of. 13 

melting point of. 131 

naval, composition of. 245 

pouring temperature of. 131 

red, composition of.81,246 

fuel consumed in melting of.77,95 

loss in melting of. 73, 

76, 77,84,86,90,95,115,116,132,252 

scientific management of. 249 

yellow, composition of. 245 

loss in melting of. 85,86, 

90,93,97,99,103, 111, 112,113,116,119,206 

pouring temperature of. 131 

suitable furnaces for melting of-122,198 

zinc losses in {netting of. 132 

See also Alloys. 


Brass founder’s ague. See “ Brass shakes. ” 

291 






















































































INDEX 


OQO 
— « — 


Tage. 

Brass founding, health conditions In. 257 

Brass foundry, Insanitary features of. 25S 

Brass industry, number of Arms In. 9 

Brass plants, variation in site of. 9 

•• Br.is> -Irtki', " MM flf. 

effects of.200,Mi 

immunity from. 200 

means of preventing.264,266 

prevalence of. 262 

symptoms of. 258 

Brasseur, M., on oil and coke furnaces. 180 

Briquet t ing of borings. 233 

Bronte, gear, composition of. 245 

leaded, composition of. 245 

loss in melting of. 10,93-95,109 

manganesp, melting of, consumption of 

fuel in. 95 

loss in. 93-95,109 

suitable furnace for.122,198 

melt ing of, number of firms engaged in.. 9 

See al*o Alloys. 

Buchanan, J. F., on fuel consumption in 

brass furnaces.33,38 

on cupola furnaces. 27 

Bulmahn, E. F., on use of producer gas. 182 

Bureau of Mines, work of. 211 

Burgess, Q. K., on boiling point of tine. 128 

Burners, atomizing, air for. 188,190,192 

high pressure.58-65,192 

low pressure. 68,59,62,63,189 

combination, merits of..191,192 

steam for.189,190 

types of. 187,188,191,192 

diaphragm, for surface combust ion.... 216,217 

fuel oil, construction of. 102,110 

use of. 74 

needle-valve, for oil furnace, advantage of. 110 

Burns, prevention of. 273 

treatment of.. 277 


C. 


Campbell, J. F., on gas furnaces for melting 

gold. 40 

Carpenter, H. C. H., on absorption of gas by 

metals. 143 

on pouring temperature of aluminum 

bronze. 131 

Carpenter, R. C. t on value of flue gases from 

oil fuel.136,137 

Carr, W. M., on use of small open-hearth fur¬ 
naces. 205 

Casters, brass, duties of. 77 

length of service of. 263 

mortality from consumption among. 263 

Castings, light, melting of. 85 

Charges for furnace, analyses of. 46, 

48,50,52,54,56,58,60,62,64,66,68 

composition of. 46, 

48,50,52,54,56,58,60,62,64,66,68 

ut ilizat ion of borings in. 232 

Chemists, for foundries, need of. 248 

Child labor in foundries, rarity of. 284 

Clamer, 0. H., on absorption of sulphur by 

copper. 147 

on electric brass furnaces. 211 

on fuel consumption of brass furnaces.... 31, 


32,34,35 


I‘age. 

Clothing for fmmdrymen, laws regarding. 279 

washing of, provision for. 280 

Cu.il, iiti.il\ . • • f . 54,115 

bituminous, use of, in reverberatory fur¬ 
nace.68,60 

partly burned, utilization of. 231 

powdered, for open-llama furnace. 213 

for reverberatory furnace. 213 

flatno from, regulation of. 212 

fuel efficiency of. 213 

possibility of using. 212 

recovery of, from ashes. 231 

volume of flue gases from. 137 

Cool furnaces, brass melting in, results of... 46-69 

notes on. 70,78,89,108,109 

comparative test of. 89 

consumpt ion of fuel in. 32, 

33.51.53.55.108.109.137 

features of. 200 

life of crucible in..‘.51,53,55 

curves showing. 158 

life of lining in.51,53,55 

melting losses in. 32,33,51,53,55 

output of. 121 

relation of size of, to fuel efficiency,curves 

showing. 170 

to melting speed, figure showing. 153 

speed of melting in.51,53,55 

figure showing. 154 

tile lining for. 78 

Coke, analyses of. 46,48,50,56,72,92,116 

as furnace fuel, advantages of.73,102 

by-product, value of. 178 

metallurgical, advantages of. 178 

recovery of, from ashes. 231 

space, relation of, to furnace efficiency... 176 

volume of flue gases from.». 137 

Coke furnace, brass melting in, results of.46-69 

notes on. 70,72,75,76, 

78,81,85,86,89,100,101,110,114,116 

comparative test of.76,89 

results of. 70 

consumption of fuel in.30-34, 

47.49.51.57.110.116.137 

dimensions of stack for. 78 

life of crucible in. 47,49,51,57 

curves showing. 159 

life of lining in. 47,49,51,57 

loss in melting in. 30,31,47,49,51,57 

merits of. 73,75,81,85,86,100,101,114 

output of. 121 

relation of size of, to fuel efficiency,curves 

showing. 169 

to melting speed, figure showing .... 152 

speed of melting in. 47,49,51,57 

figure showing. 154 

Combustion, complete, conditions deter¬ 
mining. 124 

space required for. 193 

Combustion chamber for oil furnaces, size erf. 194 

Compressed air, use of, for atomization. 189 

Concentration of wastes, methods used for... 236 
Consumption, death rate from, among brass 

workers. 261 

among casters... 263 

Copper, amount of, consumed for alloys. 12 

boiling point of. 123 










































































































INDEX. 


293 


Page. 

Copper castings, loss in melting of. Ill 

fumes, possible poisonous effects of. 259 

in rolling-mill ashes, recovery of. 237 

loss in melting of. 112,113 

molten, removal of gases from. 147 

sulphur in, effect of. 145,147 

Copper-zinc alloys. See Alloys, copper zinc. 

Core ovens, heating of, by waste heat. 226 

Corse, V. M., on use of crucible cover. 141 

on fuel consumption of brass furnaces.... 31,33 
Cottrell process for recovering fumes, use of, 

at foundries. 243 

Cowell, G. B., on effects of brass shakes. 263 

Crucibles, covers for. 265 

figure showing;. 265 

feeder for, use of. 72,223 

fuel required for different sizes of. 72 

life of. 46-69,72,74,79,95, 

100,102, 111, 113,113,120,156-161,207 
conditions governing... 80,100,161,164-166 

method of prolonging. 164 

relation of, to size, curves showing... 158, 

159,160 

loss in charging of, prevention of. 232 

loss of metal in melting in. 72 

methods of lifting. 164 

old, utilization of. 234 

proper care of. 161 

protective coatings for. 165 

relative costs of. 75 

size of, relation of, to fuel efficiency.... 151,152 

small, advantages of. 72 

types of. 194 

Crucible furnace, comparative test of. 89 

gas absorption in, prevention of. 148 

loss of metal in. 79 

merits of. 83,84,86 

relation of fuel efficiency to size of, curves 

showing. 172 

speed of melting in, figures showing. 155 

volume of flue gases from. 138 

Crucible tongs. See Tongs. 

Cupola furnaces, commercial use of. 28 

fuel burned in. 17 

use of, for brass melting. 27 

Curry, B. E., on absorption of gases in metals. 144 


D. 

Dahm, A., on use of oil distilled from coal tar. 187 
Damar^ay, E., on volatility of zinc in vacuum 130 

Damour, E., on gas-fired furnace. 30 

Danger signals, use of. 278 

Danger signs, use of. 2S5 

De Heen, M., on velocity of gases. 135 

Dean, W. R., on form of reverberatory fur¬ 
naces. 26 

on electric furnaces. 211 

on fuel consumption in brass furnace.... 32 

Delachanal, B., on absorption of gases in met¬ 
als. 145 

Demesso, J., on test for oxidation of metal... 125 
Diaphragm burner. See Burner, diaphragm. 
Dioderichs, II., on volume of flue gases from 

fuels.136,137 

Diseases of foundrymen, causes of. 257,260 

prevent ion of. 264,266,268.269,271,278,280 


Page. 

Douglas, J., on utilization of waste heat. 230 

Draft, regulation of, importance of. 177 

Dresser, H. W., on efficiency of labor. 257 

Dust, foundry, utilization of. 234 

metallic, injurious effect of. 270 

precautions against. 271 

E. 

Edwards, C. A., on absorption of gas in 

metals. 143 

on pouring temperature of aluminum 

bronze. 131 

Electric furnaces, development of, factors 

affecting. 209 

efficiency of. 210 

for brass melting, types of.18,211 

interest of operators in. 210 

labor cost of melt ing in. 209 

loss of metal in. 209 

speed of melt ing in. 209 

Electric power, cost of. 210 

Ellis, A. B., on utilization of waste heat. 201 

F. 

Feeder for crucible, use of. 72,223 

Fery, M., on fractional distillation of brass 

alloys. 127 

Finney, J. II., on utilization of fuel oil. 185 

Fitzgerald, F. A. J., on electric brass furnace. 211 

Flame, definition of. 216 

Flue dust, recovery of copper from. 243 

recovery of zinc from. 242 

Flue gases, volume of, from fuels. 136,137 

from various furnaces. 138 

Fluxes, use of, advantages of. 141 

disadvantages of. 141,142 

value of, in reducing gas absorption. 149 

Forced-draft furnaces, details of.31.32,51,57 

disadvantages of. 87 

relation of fuel efficiency to size in, curves 

showing. 171 

relative merits of.S7,179 

Foundries, average length of working day at. 281 

heating of. 267,268 

with waste gases. 227,229 

humidity of air in, regulation of. 268 

lighting of. 272 

posting of danger notices in, practice re¬ 
garding. 2S4 

proper construction of. 267 

Foundrymen, medical inspection of. 2S1 

precautions for. 275 

supplies for. 280 

Fuel consumption, keeping of records of. 255 

relation of, to size of furnace, curves 

showing. 173 

Fuel efficiency, average, of brass furnace. 11 

relation of, to sizo of furnace. 168 

curves showing. 169-172 

Fuel loss, keeping of records of. 254 

Fuel oil. See Oil fuel. 

Furnace charges, utilization of borings in.... 232 

Furnace construction, keeping of records of.. 254 

Furnace efficiency, keeping of records of. 255 

Furnace gas, composition of. 99 

temperature of. 99 

velocity of, effect of. 135 



































































































294 


INDEX 


Tag*, 

Furnace lining, cost of. 79 

composition of.. HO 

life of.*6-00,108 

material for. 166,167 

thickness of. 166,167 

Furnace losses, causes of. 251,252 

Furnace operation, records of, need of keeping 252 

standardisation of. 251 

Furnace practice, scientific control of. 249 

Furnace records, details to be kept in. 254 

number of plants keeping. 253 

Furnaces, choice of. 250 

classification of, basis of. 19 

data on, number of firms supplying. 15 

reliability of.15,16 

scope of. 13,14 

efficiency of, definition of. 123 

factors determining. 123 

hearth area of, relation of, to tonnage. 151 

large versus small, cost of operation of.. 207,208 

results of operation of. 206 

selection of, factors governing. 123 

shape of, effect of. 88 

types of, in use. 17 


See also Coal furnace, Coke furnace, Cruci¬ 
ble furnace, Gas furnace, Natural-gas 
furnace, Oil furnace, Pit furnace, Fro- 
ducer-gas furnace, Reverberatory fur¬ 
nace, Tilting furnace. 


G. 


Garland, C. M., on air supply of gas furnaces.. 215 


Gas, blast-furnace, possibility of using. 183 

Gas fuel, relative cost of. 84 

See also Illuminating gas, Natural gas, 
Producer gas. 

Gas furnace, advantages of.114,180,181 

consumption of fuel in. 40,39,106 

disadvantages of. 81 

melting loss in. 39 

speed of melting in, figure showing. 155 


Gas-generating furnaces. See Semiproducer 
furnaces. 


Gases, absorption of, by metals. 142, 144,148 

effect of, in metal. 147 

elimination of, in metal. 147,148 

See also Flue gases, Furnace gases. 

Gasoline, precautions in use of. 276 

German silver, average composition of. 115 

Gill, A. H., on volume of air for various fuels. 136 

Gloves for furnace tenders, use of. 276 

Goggles for furnace tenders, use of. 272 


Goodenough, F. W., on use of high-pressure 


gas. 140 

Gouvy, A., on use of blast-furnace gas. 183 

Gowland, W., on cupola furnace in Japan ... 28 

Grebel, A., on test for oxidation of metal. 125 

Greenwood, n. C., on boiling point of copper. 128 
Gresham, W., on melting In cupola and re¬ 
verberatory furnaces. 27 

Guichard, M., on absorption of gases in copper 145 
Guillemin, G., on absorption of gases in 

metals. 145 

Gun bronze, composition of. 105 

Gun metal, composition of. 245 

losses in melting of. 86,94,109,132 

melting point of. 131 

pouring temperature of. 131 


H. 

Hallow ell, R., on absorption of gases in cop¬ 
per. 146 

Ilampe, W., on absorption of gases in copper. 146 

Hansen, C. A., on efficiency of tilting, open- 

flame furnaces. 38 

on electric brass furnace. 211 

on fuel consumption and metal losses... 251 

on vapor pressure of brass alloys. 126,127 

Havard, F. T., on protective coating for 

crucibles. 165 

Hayden, H. O., on absorption of gases in 

copper. 146 

Hayhurst,E. H., on effects of brass shakes... „ 261 

on limiting work of foundrymen. 282 

on poisoning from brass dust. 271 

Health precautions at foundries. 264, 

266,269,271,278,279,281,283,284,286 

Heat, loss of, in waste gases. 214 

waste, utilization of. 222-224 

need for. 118 

precaut ions necessary in. 231 

Heating of foundries, indirect method of. 228 

by hot water. 229 

by steam. 229 

Ilempelmann, E., on absorption of gases in 

copper. 146 

Hering, C., on electric brass furnace. 211 

on fuel consumption in brass furnaces... 31, 


32,34,35 

Heyn, E., on absorption of gases in copper... 146 
Ilioms, A. II., on reverberatory furnaces.... 26,38 


on pit furnace. 22 

on recovery of zinc oxide. 242 

Hoffman, F. L., on mortality from consump¬ 
tion. 261 

Hoffman, II. B., on absorption of gases in 

copper. 146,147 

Horner, J., on forced-draft tilting coke fur¬ 
nace. 28 

on preheating air for combustion. 225 

Hospitals for employees, need of. 281 

Hudson, O. F., on volatilization of zinc. 128 

Hughes, G., on concentration of wastes. 237 

on fuel consumption in brass furnace.'... 34 

on use of producer gas. 182 

Hiiser, F., on gases absorbed by copper. 147 


I. 

Illuminating gas, furnaces using, details of.. 61 


heating value of. 10 

use of, in melting brass. 120,182 

volume of flue gases from. 137 

Irish, —., on supply of fuel oila. 184 


J. 


Japing, E.,on coke furnace. 20 

on fuel consumption in brass furnaces .... 34,39 

Jigs, use of, in concentrating wastes. 237 

Johnson, F., on absorpt ion of gas by metals... 146 

Johnson, N., on fuel consumption in gas fur¬ 
nace. 39 

Johnson, W. McA., on electric brass furnace. 211 
Jones, J. L., on efficiency of tilting, open- 

flame furnaces.37,38 

on use of fluxes. 141 

on use of scrap. 234 























































































INDEX 


295 


K. Page. 

Karr, C. P., on fuel consumption of brass 

furnace. 34 

on pouring temperature of brass. 131 

Kinzbrunner, C., on surface combustion. 216 

Krause, H., on coke furnace. 20 

on fuel consumption in brass furnaces.... 34,39 

Krom, L. J., on electric furnace. 211 

on oil furnace. 224 

on recovery of zinc oxide. 243 

Kropff, A. H., on relation of specific gravity 
and heating value of oil. 1S4 

L. 

Labor, average length of day for. 281 

Labor cost, keeping of records of. 254,255 

Ladles, desirability of heating. 203,204,219 

proper method of filling. 274 

Langdon, P. H., on electric furnace. 211 

on utilizing waste heat. 226 

Lathrop, W. S., on consumption of copper in 

brass making. 12 

on melting loss in brass furnaces. 32 

Lead poisoning in brass foundries, precau¬ 
tions against. 269 

rarity of. 269 

Lenning, P., on efficiency of oil furnace. 36 

on use of air atomizing burners. 190 

Lewes, V. B., on use of fuel oil in surface-com¬ 
bustion burners. 218 

on volume of flue gases from petroleum.. 136 

Light in foundries, need of sufficient. 273 

Lights, electric, for foundries. 273 

Lining, furnace, composition of. 110 

cost of. 79 

life of. 46-69,168 

material for. 166,167 

thickness of. 166,167 

Lohr, J. M., on absorption of gases in metals. 144 
on boiling points of copper-zino alloys.. 128 

on pouring temperatures of alloys. 130 

Longmuir, P., on loss of zinc in melting alloys. 132 

on pouring temperature of gun metal.... 131 

Lucke, C. E., on surface combustion.215,216 

M. 

McKinnon, H. P., on pit, oil furnace. 36 

McI’hee, II., on tilting, open-flame furnace.. 37 

on fuel consumption in brass furnaces.... 32 

Mache, II., on surface combustion. 216 

Machinery, dangers from, precautions against. 277 

safeguarding of. 277 

Magnetic separators, for waste concentrating 

"£lant, need of. 241 

Manganese bronze. See Bronze, manganese. 

Marteil, V., on crucible hoists. 164 

on fuel consumption in brass furnace.. 31,34,38 

on preheating of air in furnace. 225 

on reverberatory furnaces. 26 

on tilting coke furnace. 29 

Mathewson, E. P., on relation of hearth area 

to tonnage. 151 

on use of air for atomization. 189 

on use of waste heat in reverberatory fur¬ 
naces. 230 

Meade, R. K., on use of powdered coal.212,213 

Medical inspection, legal requirement of. 2 S 1 

monthly, advantage of. 281 


Page. 

M£ker burner, features of. 215 

Melting, speed of, conditions affecting. 150 

effect of. 149,150 

relation of to weight of charge, figure 

showing. 157 

Metal, pouring of, dangers in. 274 

Metal losses, keeping of records of. 255 

See also various furnaces named. 

Metallurgists, duties of. 248,251 

need of, at foundries. 247 

Milk as remedy for “brass shakes”. 259,265 

Moldenke, Richard, on electric furnace. 211 

Molders, proper shoes for. 275 

shoes of, figure showing. 274 

Molds, mechanical transportation of. 204 

Mond, Ludwig, on formation of carbonyls... 259 

Muntz metal, zinc losses in melting of. 132 

N. 

Natural-draft furnaces, details of. 30-33, 


47,49,51,53,55,61 

fuel consumption in. 47,49,51,53,55,61 

life of crucible in. 47,49,51,53,55,61 

life of lining in. 47,49,51,53,55,61 

melting loss in. 47,49,51,53,55,61 

relation of fuel efficiency to size in, curves 


showing. 169,170 

relative merits of. 87 

speed of melting in. 47,49,51,53,55,61 

Natural-gas fuel, advantages of. 181 

disadvantage of. 98 

heating value of. 10 

results of test with. 73 

use of, in brass furnace. 61-63,66,67 

volume of flue gases from. 137 

Natural-gas furnace, details of.61,63,67 

speed of melting in, figure showing. 61,63,67,156 

Notices, health and safety, posting of. 284 

use of. 285 

O. 

Oil fuel, advantages of. 78 

burner for, construction of. 110 

comparative cost of. 104 

consumption of. 104,105 

heating value of. 10,58,60,62,64,66,68,110 

preheating of. 225 

price of, effect of.184,185 

supply of. 186 

tests of. 70,82,93,110 

use of, factors affecting. 80 

value of, in melting brass. 105 

varieties of. 1S3,1S4 

volume of flue gases from. 137 

Oil furnaces, brass melting in, results of.46-69 

notes on. 70,71,74,75, 

76, 78-S3, 86 , 87, 89, 90, 91, 92, 96, 100, 

101,104, 105, 109, 110, 111, 114, 118, 120 

comparative test of. 70,75,76,86,89 

results of.70,76 

fuel consumption of.. 34,35,59,61,63,65,67,137 

life of crucibles in. 59,61,65,67 

curves showing. 160 

life of lining in. 59,61,65,67 

loss of metal in. 34,35, 


36-38,59,61,65,67,108,199 

merits of. 74,79,80,81, 83,85,87, 

91,92,93,96,100,101,104,105, 111, 180,1S1 







































































































296 


INDEX 


Pa«f. 

Oil furnaces, needle-valve burner for. 110 

oNjo> n ms to. 83, *7 

o j tern t ion of, factors In. 74 

output of. 121 

relation of fuel efficiency to size of, curves 

showing. 172 

speed of melting In. 59,61,65,67 

figures showing. 155,156 

types of, merits of. 71 

use of, In brass melting. 187 

Oil meter, accurate, need of. 221 

Onslow, A. \\\, on use of illuminating gas.... 140 

Open-flame furnace,details of.67^206 

diversity of opinion regarding. 196 

fuel burned in. 17 

melting of high-zinc alloys in. 198 

merits of. 70,81,85,91,105,107,196 

operation of, causes of failure in. 196 

conditions necessary for. 196 

proper handling of. 197 

quality of metal from.195,197 

relation of fuel efficiency to size of, curves 

showing. 172 

speed of melting in, figures showing-67,156 

volume of flue gases from. 138 

Oxidation of metal, effect of. 124 

prevention of. 124 


P. 


Parry, W.H., on tilting, open-flame furnace.. 37,195 
Peters, E. P., on absorption of gases in copper 146 


on recovery of fuel from ashes. 232 

on use of pow’dered coal. 212 

on use of waste heat in steam raising. 230 

Phosphor bronze, average composition of.... 115 

Phosphorus poisoning in brass foundries, 

rarity of. 269 

Pit furnace, ad vantages of. 72,73,92,100 

burners used with.21,22 

capacity of. 20 

charact eristicsof. 20 

construction of. 21 

details of.19-21 

fuel consumpt ion in. 17, 

34,35,51,53,55,59,61,70,71,98,99 

life of crucible in.36,31,47,49,59,61 

life of lining in.59,61 

melting loss in. 32-34,35,59,61,112 

merits of. 92 

operation of. 99 

results of test with. 73 

sizes of. 22 

small, melting in, details of. 206 

speed of melting in. 31,32,51,59,61 

figure showing. 155 

use of, at rolling mills. 202,203 

volume of flue gases from. 138 

Popoff, S. J., on boiling point of copper-zinc 

alloys. 128 

Pouring from ladle, method of. 204 

objection to. 203 

Pouring gang, usefulness of. 76 

Pouring room, ventilation of, need of. 267 


Pouring temperature, proper, determination 


of. 


220 


Powdered coal. See Coal, powdered. 


Pag*. 


Preheater “hood," use of. 223 

Primrose, If. 8., on absorption of gases in 

metals. 145 

on employment of metallurgists. 248 

on fuel consumption of brass furnaces.... 31 
on pouring temperature of gun metal.... 131 

on reverberatory furnace. 39 * 

Producer gas, composition of. 106 

beating value of. 10 

suitability of, for melting brass. 139 

use of, in brass furnaces.61,182,183 

volume of flue gases from. 137 

I’roducer-gas furnace, brass melting in,results 

of.. 61 

metal loss in, cause of. 106 

Pyrometers, development of, need of. 220 

use of, for molten brass. 220 

value of. 220 


Q. 

Quigley,W.S., on tilting open-fjamefumaces. 37 

on natural-draft, pit furnaces. 31 


R. 


Rambousek, J., on effects of brass shakes.... 261 
Rawlins, J. W., on reverberatory furnace 

using powdered coal. 212 

Raymond, A. W., on use of powdered coal.. 212 

Reardon, IV. J., on tilting open-flame fur¬ 
nace. 37 

on fuel consumption of gas furnace. 39 

on pouring temperature of alloys. 131 

on use of oil and natural gas in furnaces.. 139 
Records of furnace operat ion, keeping of... 250-255 

Recuperative furnace, construction of. 99 

“Reducing" atmosphere,maintenance of, in 

electric furnace. 209 

need of information regarding. 221 

“Reducing flame," definition of. 214 

Redwood, B., on steam for atomization. 1S9 

on size of combustion chamber. 194 

on types of oil burners. 193 

Refuse, foundry, refining of. 240 

treatment of. 230-240 

smelting of. 241 

fluxes for. 241 

Reichhelm, E. P., on fuel consumption of 

brass furnaces.32,34 

Reidenbach, R. W., on utilization of waste 


gases. 229 

Respirators, use of. 264,271 

Reverberatory furnace, comparative test of.. 89 

details of. 26,27,69,90,91. j}2 

fuel consumption of. 17,38,39,60.90 

fuel efficiency of. 199 

life of crucible in. 00 


life of lining in. 69 

melting loss in. 38,39,69,108,199 

merits of.39,112,115 

relation of fuel efficiency to size of, curves 

showing. 172 

results of test with. 89 

speed of melting in. 69 

figure showing. 156 

use of.38.199 

extent of. 26 

volume of flue gases from. 138 







































































































INDEX. 


297 


Page. 

Reversible furnace, advantages of. 223 

Reynolds, A., on preheating of air in open- 

hearth furnaces. 226 

Richards, J. W., on electric brass furnaces... 211 
Robertson, L. B., on use of illuminating gas. 182 

Rolling mill waste, treatment of. 242 

Rolling mills, furnaces in, copper content of 

ashes from. 237 

operation of.76,77 

types of. 201,202 

Rotary cement kilns, use of powdered coal in. 212 

Round furnaces, advantages of.91,173,174 

increasing use of, at rolling mills. 201 

Round versus square furnaces, merits of. 88, 

91,94,97,118,119,175 

S. 

Safety, means of promoting. 285 

Safety committee, duties of. 286 

Sand, molding, advantages of heating_. ... 268 

Sanitary conditions, maintenance of. 286 

Schenck, R., on absorption of gases in copper. 146 

Schnabel, on surface combustion. 215 

Schreiber, J., on utilization of waste heat_ 230 

Schutz, F. H., on relation of zinc loss to air 

pressure. 190 

Scott, E. K., on electric brass furnace. 211 

Scrap, utilization of. 234 

Seipke, F. W., on concentration of foundry 

wastes. 237 

Semiproducer, furnaces, description of. 28,29 

Sexton, A. II., on comparison of round and 

square furnaces. 176 

on fuel consumption in brass furnaces.. 33,36-38 

on reverberatory furnaces. 26 

on thickness of coke in furnace. 176 

Shepherd, E. S., on absorption of gas in 

metals. 143,144 

on melting point of copper-zinc alloys_ 128 

Sherman, II. C., on relation of density of oil 

to calorific value. 184 

Shrinkage. See Melting loss. 

Sieger, G. N., on electric brass furnaces. 211 

Sieverts, A., on absorption of gases in copper.. 146 

Skimming into water, danger of. 242,273 

Skimmings, percentage of copper in. 237 

utilization of. 234 

Smith, E. W., on gas and coke furnaces. 141 

Smith, J., on fuel consumption of brass fur¬ 
nace. 37 

“Soaking” of metal, evils of. 219,251 

Spelter chills. See “ Brass shakes.” 

Sperry, E. S., on absorption of gas in metals.. 143 

on briquetting of borings. 233 

on cupola furnace. 28 

on effect of sulphur in copper. 145 

on electric brass furnace. 211 

on use of fuel oil. 185 

on washing of skimmings. 240 

•*Spillings,” utilization of. 234 

Square furnaces, advantages of. 85,95,173,174 

fuel consumption in. 85 

use of.97,195 

Square versus round furnaces, merits of. 88, 

91,94,97,118,119,175 

Stack for furnace, dimensions of. 78,103 

Stahl, —., on absorption of gases in copper... 146 


l'age. 

Steam heating, with waste gases, advan¬ 


tages of. 229 

Steam raising, use of waste heat in. 230 

Stefan, J., on relation of pressure to rate of 

volatilization. 133 

Strohm, R. T., on types of oil burners. 193 

Sulphur, absorption of, by copper. 147 

elimination of, in electric furnace. 209 

Surface combustion, application of, to brass 

melting. 217 

essentials of. 215 

industrial development of. 216 

possibilities of. 218 

T. 

Tapping furnaces. See Tilting furnaces. 

Tar, oil distilled from, use of. 187 

use of, in brass melting. 187 

Teclu, H., on surface combustion. 216 

Temperature of pouring metals. 219 

Thermal efficiency of furnaces, low, causes of.. 213 

Tilting furnace, advantages of. 74, 

75,79,111,119,180 

details of.23,24 

disadvantages of. 78,178,180 

fuel consumption of. 17, 

33,34,36-38,57,63,65,67 

life of crucible in. . . 57,63,65,67 

life of lining in. 57,63,65,67 

melting loss in. 36-38, 

57,63,65,67,77,179,180 

results of test with. 89 

speed of melting in. 57,63,65,67 

types of.1.24,25 

use of, at rolling mills. 201,202 

volume of flue gases from. 138 

Tongs, grab type, advantages of. 163 

types of. 72,78,84,115 

description of.161,162,163 

figure showing. 162 

Turner, T., on effect of heating brass in 

vacuum. 130 

on effect of pressure on zinc losses. 133 


U. 

United States Naval Liquid-Fuel Board, 

burner devised by. 1C2 

Upton, G. B., on absorption of gas in 
metals. 143,144 


V. 


Vanners for separating waste, use of. 236,238 

Ventilation of foundry, importance of. 266 

natural versus forced. 267 

Volatilization of zinc, factors affecting. 133,134 

formula for. 134 

of liquids, formula for. 133 

W. 

Wallace, R. B., on briquetting of borings- 233 

Waste, concentration of. 236 

method of separating. 235 

recovery of metal from. 234 

Waste gases, loss of heat in. 214 

need of information regarding. 221 

use of, in heating foundry. 227 




























































































298 


INDEX 




Waste heat, utilization of. 222,223 

need fur. |1 B 

precautions necessary in. 231 

Water, preheating of, for boiler, use of waste 

heat in. 230 

Water supply, purity of, Importance of. 280 

Webster, W. R.,on fuel consumption in brass 

furnace. 32 

Weeks, C. A., on electric brass furnace. 211 

on fuel consumption of brass furnaces.... 37 

Weintraub, E., on absorption of gases in 

metals. 145 

Welfare work by employers, advisability of.. 2S6 

Wilfley tables, use of, for concentrating 

wastes. 236 

Wittich, L. L., on concentrating systems for 

wastes. 238 

Women at foundries, employment of. 284 

Wood, It. A., on fuel consumption in brass 
furnaces. 32 


Page. 

Wood, It. A., on life of crucibles. 166 

on natural-draft pit furnaces. 31 

Woods, 8. H., on absorption of gases in 

metals. 144 

Wood, W. D., on use of powdered ooal. 213 

Z. 

Zinc, boiling point of. 125,128 

fume, prevention of toxic eifects of. 265 

losses of, at Waterburv, Conn. 119 , 

determination of rate of. 125 

effect of pressu re of gases on. 133 

factors affecting. 138 

in open-flame furnace. 103,198 

melting of, precautions in. 273 

pouring of.. 265 

volatilization of, in vacuum. 130 

relation of pressure to. 134 

Zinc oxide, as cause of brass shakes. 259 

recovery of. 242 



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